Of all the class of 2012 players up for extensions on their rookie deals, none may be in a more fascinating position than Harrison Barnes, who reportedly just turned down a four-year, $64 million offer from the Golden State Warriors. Barnes has been up-and-down in his first three seasons in the NBA, but he has played at his best when the lights are brightest in the playoffs. The question he will have to ask himself is how much more room does he have to grow as a player and whether or not that can happen in Golden State. Does he want to take a lot of money to be a cog in a championship team or roll the dice under the assumption that he can become a featured player somewhere else?

When looking at Barnes career as a whole, the first thing that jumps out to me is that the best stretch of play came all the way back in his rookie season, when he was filling in for David Lee as a small-ball PF during the 2013 playoffs. That was the year this version of the Golden State Warriors put themselves on the NBA map, stunning the 57-win Denver Nuggets in the first round and taking the San Antonio Spurs to six games in an extremely competitive second-round series. Barnes was a revelation in that role, looking like the player his recruiting rankings had suggested he would become.

When he’s playing as a power forward, Barnes has an edge in speed, shooting and ball-handling ability against the vast majority of his opponents. The defense, meanwhile, is stretched farther out, as there is one fewer big man playing in the lane and more room for Barnes to operate off the dribble and attack the rim. He has a better chance of being a more dynamic offensive player because he is creating mismatches in a way that he doesn’t as a SF. That’s essentially what Golden State assistant coach Luke Walton said in this fantastic profile of Barnes from Lee Jenkins in Sports Illustrated during last year’s playoffs:

“He’s not only very strong, to the core strong, but he’s very quick,” says Walton. “So he can use that to his advantage too. We feel like big guys battling against Harrison, as strong as he is, isn’t as much of an advantage as them trying to guard Harrison on the other end with how quick he is and shooting from the outside.”

At 6’8 225 with a 6’11 wingspan, Barnes has fairly average size for a starting NBA small forward. Barnes will never be able to match Kevin Durant, the offensive standard bearer at the position, but even in comparison to guys like Chandler Parsons and Rudy Gay, he doesn’t stand out in his ability to create off the dribble, shoot from the perimeter or run the offense. He’s a 3-and-D player who can serve as a complementary piece on both sides of the ball. In that capacity, he doesn’t look like the type of guy who should be turning down extensions worth upwards of $15 million a year.

Even on the other side of the ball, where lack of high-level feel isn’t as important as all-around athleticism, Barnes doesn’t really stand out as a defender on the perimeter. Andre Iguodala and Klay Thompson often get the more high-profile defensive assignments while Barnes is asked to be just another cog in the Warriors switch-happy schemes. In the NBA Finals, LeBron James seemed to relish every opportunity to go up against Barnes, which caused Steve Kerr to adjust as the series went on and put Iguodala on him more and more.

Where Barnes differs from Iguodala and Thompson is the way in which he can guard bigger and more traditional post players. He is bigger than both of them and he is solidly built with the ability to position himself and prevent from being overwhelmed at the point of the attack. One of the keys to Golden State’s comeback in their 2nd round victory over the Memphis Grizzlies was Kerr’s shuffling of the match-ups after Game 3, sliding Draymond Green to Marc Gasol and Barnes to Zach Randolph and having Andrew Bogut roam the paint as a help-side defender rather than guard Tony Allen.

For as well as Green battled in the post all season long as an undersized PF, he really struggled in the 1-on-1 match-up with Randolph, his fellow Michigan State big man and a guy completely impervious to Green’s physical brand of defense. Randolph’s production dipped dramatically after the switch was made in Game 3, which can’t just be credited to Barnes but which does show his ability to hold up defensively against one of the best post players in the league:

Every 1-on-1 match-up is different and just because Barnes was able to hold down Randolph certainly doesn’t mean he could do the same against guys like Blake Griffin and LaMarcus Aldridge. However, the underlying logic is still the same - if you are going to pound the mismatch in the post, we are going to come at you the other way with the pick-and-roll and let’s see which approach is going to generate the most efficient offense over the course of the game. That was the basic idea behind the Warriors starting the 6’6 Draymond Green at the position.

The distinction between what Barnes and Green were doing at each forward spot on offense might seem like splitting hairs but it really isn’t. Green gets the benefit of playing next to three true perimeter players who have to be marked on the three-point line and can create off the dribble and attack a close-out. Defenses don’t have to respect Green as much from the perimeter, which means less room for Barnes to maneuver. We are talking about slivers of difference but those slivers might be worth millions of dollars to the right team.

To be sure, Barnes isn’t nearly as good a rebounder or a playmaker as Green and he doesn’t have the type of versatile all-around game that will allow him to contribute at a high-level on nights when his shot is off. Running Barnes as a full-time PF would be more akin to the Toronto Raptors playing DeMarre Carroll at the 4 or the Indiana Pacers sliding Paul George down a spot in the line-up. The league is moving from stretch 4’s to playing 3’s as a 4’s and just waving their hands at the very idea of even trying to match size at the position. If Barnes is ever going to be worth the type of money that he wants, it will be from being at the forefront of that trend. I thought this quote from Warriors assistant Ron Adams in the earlier mentioned SI piece summed it up well:

“He likes guarding people in the post,” says Adams, who foresees a league full of Harrison Barnes' in the future. [Emphasis mine] “I think the way our game is progressing it’s going to be demanded of a lot of people,” he says.

Given his lack of ideal size, a team that started Barnes at the 4 would want a true Goliath at the 5, someone who could vacuum up every rebound and prevent their team from being completely out-massed on a nightly basis. One situation that would be interesting for Barnes would be playing with the Detroit Pistons and Andre Drummond. Switch out Ersan Ilyasova for Barnes and the Pistons would take the 4-out revolution to its next logical step - surround a 7’0 with 4 wings and go all pick-and-roll all the time.

The ideal role for Barnes in the modern NBA would probably be as the biggest wing in that scenario.

Playing in Golden State, where they just gave Draymond Green an $84 million extension to fill that role, means that Barnes will probably never reach his ceiling as a player if he stays put. And with Steph Curry and Klay Thompson dominating the ball, he’s certainly not going to get many more opportunities to be an offensive creator on the perimeter. Barnes is a very expensive luxury for the Warriors, albeit one that a big-market team that just won a championship can certainly afford to pay.

Golden State needs Barnes at the 4 when Green goes to the 5, which was the killer app line-up they used in the playoffs when they wanted to go for the kill. What they have to figure out is whether they want to pay a guy who can be a good contributor in the role they normally use him at but could be a great one in a different role. That’s the key for any salary negotiation - it’s not what a guy is worth but how are we going to use him.