In the NBA, the gap between “bad” and “good” isn’t nearly as wide as the one between “good” and “great”. Building a good NBA team isn’t all that difficult: 27 of the league’s 30 franchises have made the playoffs in the last five seasons. But while getting in is easy, advancing is not.

Very rarely do teams reach the Conference Finals without being great on one side of the ball. Great offenses are built around at least one All-NBA caliber scorer who can command a double team, while great defenses are built around at least one big man who can protect the rim at a high level.

The second round is typically the ceiling for teams without either type of player: the Joe Johnson/Josh Smith Atlanta Hawks have won three first-round playoff series, but have gone only 2-12 in the second. While Atlanta lost in the first-round this season, there should be a similar winnowing process in 2012, as the NBA’s top teams separate themselves from the pack.

1) Oklahoma City vs. LA Lakers:

The tables have turned since the 2010 first-round series between the two. Lamar Odom, Shannon Brown and Derek Fisher are no longer with the Lakers, while all four of Oklahoma City’s stars (Kevin Durant, Russell Westbrook, James Harden and Serge Ibaka) have improved dramatically. The Lakers size could still give the Thunder some trouble, but their lack of perimeter shooting may be their undoing.

The key match-up: There could be a changing of the guard at the shooting guard position; James Harden was in middle school the first time Kobe Bryant made the All-NBA first team. Basketball is a young man’s game, especially on the perimeter, and the 22-year-old may be ready to pass the 33-year-old.

The prediction: Oklahoma City in 5.

2) San Antonio vs. LA Clippers:

There was no team happier to see Memphis lose than San Antonio, who struggled against the Grizzlies size in their first-round loss last year. The Clippers' raw young frontcourt doesn’t pose nearly the same threat, and if the Spurs can keep the game in the halfcourt, their superior offensive execution should get them to the Conference Finals for the first time since 2008.

The key match-up: With San Antonio likely to force Blake Griffin into becoming a jump-shooter, Chris Paul will once again have to carry a gargantuan load offensively for Los Angeles. However, Paul won’t be able to rest defensively in this round, as Tony Parker and Manu Ginobili will test his lateral quickness in ways Mike Conley and OJ Mayo couldn’t.

The prediction: San Antonio in 5.

3) Miami vs. Indiana

Chris Bosh’s injury makes this series more interesting, but Indiana doesn’t have enough up front to defeat LeBron James. The common denominator in his playoff defeats has been an elite 6’10+ rim protector (Rasheed Wallace, Tim Duncan, Kevin Garnett, Dwight Howard, Tyson Chandler), and the Pacers frontcourt, while skilled, doesn’t have an above-the-rim player.

The key match-up: Miami’s one defensive hole is at the center position, where they’ve been trying to get by with four power forwards (Bosh, Joel Anthony, Udonis Haslem and Ronny Turiaf). They don’t normally play anyone who can handle the 7’2 Roy Hibbert, and if Hibbert can force the Heat to put Dexter Pittman on the floor, it would be a big win for Indiana.

The prediction: Miami in 5

4) Boston vs. Philadelphia:

Derrick Rose’s injury completely changed this side of the bracket, extending Boston’s window of contention and possibly opening one for Philadelphia. The 76ers have the athleticism to match the Celtics on the perimeter, but they don’t have any frontcourt players who can handle Kevin Garnett’s size and shooting ability. In his 17th season in the NBA, Garnett has silenced doubters, like me, with dominant two-way performances in the playoffs, including a 29 point and 11 rebound effort in Game 1.

The key match-up: Jrue Holiday, who is still only 21-years-old, is one of the best young point guards in the NBA. For Philadelphia to have any chance at pulling off a second consecutive upset, he’ll need to take the next step as a player and solidly win his match-up with Rajon Rondo. In Game 1, Rondo had a triple-double while Holiday scored 8 points on 3-13 shooting.

The prediction: Boston in 5