With injuries to Russell Westbrook and Derrick Rose dramatically weakening two of their biggest challengers, there aren’t many obstacles left in the path of the Miami Heat.

After a methodical sweep of the Milwaukee Bucks in the first round, their playoff record is now 26-7 with the Big Three in the starting line-up. In a league becoming more perimeter-oriented, the Heat have the ultimate small-ball frontcourt, with Chris Bosh and Shane Battier spacing the floor for LeBron James. You can’t defeat Miami by playing their game, which is why the massive front-lines of the Indiana Pacers and Memphis Grizzlies are the biggest threat to the NBA’s newest dynasty.

While most of the league zigged, the Pacers and Grizzlies zagged. Instead of moving towards a four-out offense that spaces the floor for pick-and-rolls and dribble penetration, they run their offense through two skilled big men in the post. As a result, they have remarkably similar rosters and styles of play. They prefer to operate in the halfcourt, pounding the ball inside and grinding out possessions defensively. Even more intriguingly, they both face a challenge in the second round that could prepare them for the Heat: a clash of styles against the second (Kevin Durant) and third (Carmelo Anthony) best small-ball 4’s in the NBA.

A generation ago, most front-lines looked like Zach Randolph/Marc Gasol and David West/Roy Hibbert. Randolph (6’9 260) and West (6’9 250) are two of the toughest power forwards in the NBA, old school players who can brutalize smaller defenders on the block as well as step out and knock down a 15-foot jumper. Gasol (7’1 265) and Hibbert (7’2 280) are two of the league’s biggest centers, defensive anchors who can control the area around the rim and protect it at an elite level. While none of the four have three-point range, they know how to play off each other and create space while operating in the narrow confines of the paint.

With so much size upfront, it’s no surprise Indiana and Memphis are two of the slowest teams in the NBA. In the regular season, the Grizzlies averaged 88.4 possessions per-48 minutes, 30th in the league, and the Pacers averaged 90.2 possessions per-48 minutes, 25th slowest. That continued in the first round of the playoffs, with Memphis/LA Clippers and Indiana/Atlanta turning into half-court rock fights. Both teams dictated the style of the game: the Grizzlies never allowed the Clippers to get out into transition while the Hawks were forced to abandon their small-ball front-court and start Johan Petro by Game 3.

As the Knicks and the Thunder discovered in Game 1 of the second round, it’s hard to go small against power forwards as skilled as West and Randolph. New York only has two conventional big men (Tyson Chandler and Kenyon Martin) left on their roster and they prefer to use Carmelo at the 4. The problem is that leaves either Carmelo or Iman Shumpert giving up a lot of size against West, who had 20 points on 8-for-15 shooting in Game 1. And while Oklahoma City starts Kendrick Perkins and Serge Ibaka, playing both at the same time dramatically impacts their floor spacing, since other teams don’t have to defend Perkins.

The key is to attack the Pacers and Grizzlies where their size can be negated: in transition and when they go to their bench. Forcing live-ball turnovers against both is crucial, since that speeds up the tempo of the game and creates open-floor scoring opportunities. And when their big men are fatigued or in foul trouble, the opposing team has the opportunity to dictate the style of the game. The Pacers went 12 minutes without both Hibbert and West on the floor in Game 1; the Grizzlies went 14 without both Randolph and Gasol. The Thunder and the Knicks have to take advantage of the stretches of the game when they can go small with impunity.

Those stretches are where Indiana (Danny Granger) and Memphis (Rudy Gay) miss their leading scorer from last season. This season, Granger played in only five games due to a knee injury, while Gay was dealt in a salary-cap move at the trade deadline. There are plenty of differences in their games, but both are 6’9+ forwards capable of playing inside and out. Without them, neither the Pacers nor the Grizzlies can put too much firepower on the floor in the rare occasions when they go small. When Randolph was in foul trouble in their first two games against the Clippers, it was a completely different series.

Where the two teams differ is how they’ve adjusted without Gay and Granger. Indiana has run more of their offense through Paul George, their 6’8, 220 small forward. George, who won the Most Improved Player award this season, has thrived in Granger’s absence, averaging career-highs in points, rebounds and assists. Memphis, in contrast, has turned the keys over to Mike Conley, their 6’1 185 point guard. Conley is now their best shot-creator and the player they turn to in end of the clock situations. He went toe-to-toe with Chris Paul in the first round and they’ll need him to dominate his individual match-up against the Thunder, especially with Westbrook out.

If either Memphis or Indiana can get out of the second round, it will have been the perfect warm-up for an eventual series against Miami. For the most part, the Heat do everything the Thunder and the Knicks do, they just do those things better. If the Pacers let J.R. Smith and Carmelo Anthony take over the game from the perimeter, they will have no chance against LeBron James and Dwyane Wade. And if the Grizzlies can’t contain Kevin Durant when Ibaka or Nick Collison is the lone big man on the floor, good luck handling LeBron when Bosh is spotting up for corner 3’s.

Most importantly, if Memphis and Indiana can’t dictate the match-ups in the second round, there’s no way they’ll be able to do so against Miami. In the three years since “The Decision”, only one team -- the 2011 Mavericks -- has forced the Heat to stay big. Against everyone else, Miami’s postseason record with their Big Three healthy is 24-3. A generation ago, “small-ball” was an underdog strategy, a desperate attempt to even the playing field in a sport dominated by centers. That’s how much the balance of power has changed: in 2013, Goliath is the underdog.

Through two first round games, “small ball” has been one of the big themes of the NBA Playoffs. The Golden State Warriors were left for dead when they lost David Lee, but they completely flipped the dynamic of their series with the Denver Nuggets in Game 2, when they started Harrison Barnes at power forward and spread the floor with four perimeter players.

The Houston Rockets, after being blown off the court by the Oklahoma City Thunder in Game 1, made a similar adjustment with Chandler Parsons and came this close to pulling off the upset in Game 2. Going small is the easiest adjustment a coach can make, as it instantly creates the floor spacing necessary for offenses to function.

The trade-off for that extra spacing comes on the other end, where a smaller frontcourt can be exploited on the low block and the offensive boards. However, with fewer traditional big men left who can take advantage of a size mismatch, it’s a lot easier to start swingmen at power forward. As a result, the power forward position dictates the tempo and style of a series. Zach Randolph versus Blake Griffin is why Memphis Grizzlies/Los Angeles Clippers is a halfcourt brawl in the 80’s; Wilson Chandler versus Harrison Barnes is why Warriors/Nuggets is a free-flowing shootout in the 110’s. To change the rules of engagement, all a coach has to do is switch out his power forward.

Teams with traditional 4’s, like Randolph and David West, have to slow the pace of the game down and grind away smaller teams in the halfcourt. Conversely, teams with small-ball 4’s, like the Nuggets, almost always want to speed up the tempo and try to attack in the open court. The best teams in the NBA can do both: they can spread the court on offense without sacrificing much on the defensive end because of the versatility of a star forward. That’s what makes LeBron James and Kevin Durant so scary; the best two players in the league just happen to play the most important position in the game.

The Miami Heat and the Thunder have the ultimate trump card: going small with their superstar small forward at power forward. More often than not, LeBron (6’9 270 with a 7’0 wingspan) and Durant (6’11 235 with a 7’4 wingspan) are the biggest, fastest and most skilled players on the floor. When they have the space to play in a 1-on-1 situation in the half-court, there’s very little teams can do to stop them. LeBron is averaging 27 points and seven assists on 56 percent shooting; Durant is averaging 28 points and five assists on 51 percent shooting. They have essentially been scoring at will this season.

That becomes even more of an issue with a jump-shooting big man at center. With Chris Bosh now extending his range out to the three-point line, Miami can stretch a defense to the breaking point any time they want. When Bosh and Shane Battier are stationed at opposite corners of the three-point line, the opposing team’s two biggest players have defensive responsibilities 25+ feet from the basket. That’s not where you want them to be when LeBron is barreling towards the rim against a slower defender or bullying a smaller one on the block. The Thunder can do the same thing with Serge Ibaka at the 5.

LeBron and Durant represent a rather existential threat to any small-ball team. Miami and Oklahoma City do everything teams like Denver, Golden State and New York do, but they do those things much, much better. How can you beat the two best players in the league at their own game? Carmelo Anthony, for example, has turned himself into an MVP candidate as a small-ball 4, but he’ll have to go through the best small-ball 4 in the NBA to reach The Finals. The Knicks' offense is built around Carmelo consistently dominating his individual match-up. It’s great that he is confident when he goes up against LeBron, but it’s not going to make a difference.

Going back to 2011, only one team has beaten both the Heat and the Thunder. The key to the Mavericks success was their ability to dictate the tempo. Since Dallas played two 7’0 -- Tyson Chandler and Dirk Nowitzki -- for most of the game, neither Oklahoma City nor Miami could go small very often. Instead, they had to keep in two big men to battle with the Mavericks stars upfront. And with less space on the floor, LeBron and Durant became mortal, especially when matched up with a Hall of Fame-caliber defensive stopper in Shawn Marion.

However, ever since Mark Cuban decided to break up those Mavericks in order to start chasing waterfalls, no team has been able to recreate that blueprint. There were high hopes for the Lakers, but the injury woes of their main stars and the general lack of ability of their supporting cast has made them first round cannon fodder. The Pacers couldn’t close out a Heat team without Bosh last year; could they really beat a healthy group, this time without Danny Granger? The Grizzlies lack of perimeter firepower cost them against the Thunder in 2011 and they have even less this time around. The Nets don't have enough interior defense to be a contender.

On paper, the Spurs and the Clippers are the two teams with the best chance of preventing a rematch in the NBA Finals. However, both will have to overcome significant hurdles to beat Oklahoma City.

The Clippers' halfcourt offense has a tendency to stagnate, as they don’t have a player capable of stretching the floor at the 4 or the 5. Nor, for that matter, do they have anyone capable of matching up with Durant. San Antonio has Kawhi Leonard, but they don’t have a second big man who can prevent Oklahoma City from going small. Popovich is having trouble keeping Tiago Splitter on the floor against the Lakers, the perfect match-up for him, because the Spurs are much more effective with a four-out offense.

Barring an untimely injury, it’s hard to see LeBron and Durant not reuniting in The NBA Finals. With so many teams moving towards small-ball, there just aren’t any great low-post teams standing in their way. Basketball has always been a big man’s game, but the most dominant big men in the sport are no longer centers who operate on the low block; they’re swing forwards who can dominate from any part of the floor. While point guard gets all the hype, we are in the age of the small-ball 4. LeBron is 28 and Durant is 24; there could be a lot more Heat vs. Thunder NBA Finals in our future. Forget the second coming of Bird versus Magic, we might be looking at a 21rst century twist on Russell versus Chamberlain.

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MILWAUKEE – Sitting around the house for all those offseason months, Chris Andersen didn’t believe he would play this season. He kept lifting weights, kept shooting in the gym, but his expectation was to take the year off, fully heal the right knee on which he had arthroscopic surgery over the summer, and sign with an NBA team for next season.

When Andersen made enough progress with his knee to play this season and learned about signing with the Miami Heat, he felt grateful for another opportunity, a sense of rejuvenation after being amnestied by the Denver Nuggets in the offseason. Many teams could have used Andersen to bolster their frontcourt, but none were as proactive as the Heat to add the dimension they’ve lacked: A 6-foot-10, long-armed big body whose motor is endless even at 34.

“Going back and forth on [if] I was going to play, I really didn’t expect to play this season,” Andersen told RealGM. “I was going to let my knee heal up all the way before I could step foot back on the court and do some basketball stuff. … There ain’t no shape like getting in basketball shape, unless you’re playing basketball. I could be in the greatest shape that I could be in, but if you’re not in basketball shape, then you’re just two steps behind.”

The Heat held extensive searches as far back as last offseason to add an athletic frontcourt player, bringing in big man after big man for workouts. No one’s upside with the team intrigued Miami management as much as Andersen.

For now, Andersen has moved past Joel Anthony as the Heat’s first big man off the bench, and he continues to play catchup on schemes and offensive sets, spending time watching tape with the coaching staff before games. His knee flared up at times upon his start with the Heat, but he’s steadily increased the strength in the knee, steadily regaining full confidence in it. Gradually, Andersen has felt more comfortable on the court, with 10 points and five rebounds in 16 minutes Wednesday and five points and five rebounds in 16 minutes Friday.

“The [Heat] have a great training staff on board,” Andersen said, “and they definitely kept me in the training room, kept ice on it, kept stim on it, kept plugging away at the knee that became inflamed with all the activity.

“So over the past couple months, I’ve really gotten my body to where it has endured all of the beating and banging that I’ve been doing. I’m pretty much back into my old swing of things.”

Erik Spoelstra experimented frequently with the Heat’s rotation early in the season to find the solution he’s comfortable with over these next two to four months. There’s no plan in place to increase Andersen’s minutes – instead staying where his playing time has been recently, around 15 to 20 minutes – and the energetic big man appears part of the reserve group that Spoelstra will trust in the playoffs.

Still, Spoelstra primarily played four bench players throughout last season’s title run, and the minutes of Andersen and Mike Miller could fluctuate depending on matchups. In Friday night’s 107-94 win over the Bucks to push the Heat’s win streak to 21 straight, Spoelstra also closed out the final five minutes with his potential crunch-time lineup come playoff time: LeBron James, Dwyane Wade, Ray Allen, Shane Battier and Chris Bosh.

Andersen played a critical reserve role in playoff runs with the Nuggets, most notably in the trip to the Western Conference Finals in 2009. In his 11th season, he doesn’t know how much longer he wants to play. He’ll know whenever his activity runs empty, Andersen guesses.

“I ain’t no anchor, man,” Andersen said with a laugh. “These are all veteran guys and they know what they’re doing. I’m just thrilled to be here and being part of the defending champions and having an opportunity to win this again with this group of guys. It’s amazing to be in that situation, not taking anything for granted and staying on what I’m doing.

“It’s real special to me, real unbelievable getting the opportunity to win a championship.”

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