Harrison Barnes just played the best six games of his young NBA career.  For the underdog Warriors to have a more than a puncher’s chance in the Western Conference Semifinals against the San Antonio Spurs, he’ll need to be even better.

The pressure on Barnes isn’t as simple and superficial as that proclamation makes it sound.  Nobody is asking him to carry Golden State offensively the way they are Steph Curry, and his responsibilities in general in this series aren’t as strenuous as those of Andrew Bogut or Klay Thompson.  Barnes will be an ancillary piece this round much like he was the last one and all season long.

But his influence may prove much larger than that.

San Antonio is set in its ways.  They have a brilliant system on both ends of the floor and a great mix of players to run it; arguably no coach in the NBA gets more from a combination of strategy and personnel than Gregg Popovich.  It helps to have three future Hall-of-Famers and a wealth of dependable role players at his disposal, of course, but the Spurs success hinges on more than coach or player talent.  They’ve a true program in San Antonio, one of professional sports’ best, rooted in commitment, consistency and the potent mix of the two.

Plug and play is the Spurs motto.  They adhere to a certain set of basketball standards no matter who is on the floor.  They may change from one year to the next based on progression, regression and other measures, but San Antonio has utmost faith in the system it builds season by season.

2012-2013’s (in stark opposition to last season) has meant a staunch reliance on traditional lineups – five-man units that consist of at least two of Tim Duncan, Tiago Splitter, Boris Diaw, and DeJuan Blair.  As long as Popovich has his pair of real big men (just include Bonner for now) he worries not of San Antonio remaining trio.  The Spurs had just four lineups in the regular season that reached 100 minutes of floor-time; their normal starting and team-leading unit registered a paltry 364 minutes, making it the league’s 24th-most used group.  San Antonio’s second-most played? 153 minutes.  The third? 125 minutes.  The sixth? 65 minutes.

Plug and play.  It’s what they do.  It bears mentioning that much of that regular season variability had to do with injuries and Popovich’s reluctance to play his older stars major minutes, but the overlying point remains.  The Spurs pay little mind to faces on the court; what they care about most are positions, and this year that’s meant two-post lineups almost exclusively.

Among San Antonio’s 41(!) units that played at least 20 minutes during the regular season, only one of them utilized frontcourt small-ball the way the modern NBA does.  The remaining 40 groups – small sample size or not – all consisted of two traditional big men.  And looking at the numbers of that solitary downsized quintet, Popovich’s reluctance to play that lineup and other theoretical ones like it extended minutes makes sense.

To put it bluntly, they were bad.  Very bad.  San Antonio’s quintet of Tony Parker-Manu Ginobili-Danny Green-Kawhi Leonard-Tim Duncan played to a dismal net efficiency rating of -19.9, a mark second-to-last among the list of 41 units that played 20 minutes or more.  It’s important to note they did so in just 36 minutes of floor-time, a number miniscule enough to perhaps deem their poor showing irrelevant altogether.  But that factored with Popvich’s sheer hesitance to try other diminutive lineups means he knows something about his team’s makeup, and it’s clear he doesn’t like it.

The Spurs just don’t want to play small.

Golden State, then, needs to force their hand.  The best way to do so? An aggressive, engaged and effective Barnes.  Playing the role of nominal power forward, his blend of three-point shooting and one-dribble penetration can stretch Duncan, Splitter, Diaw, Blair or even Bonner beyond his limits as a shuffler and mover on defense.  Barnes (and Draymond Green) individually is the most direct means of exploiting the Warriors quickness advantage; the other centers around extra, skip and pop passes that force the San Antonio’s disciplined defense into inconsistent rotations.

Evidence supporting the Spurs lack of effective small-ball lineups is lacking; 36 minutes of a single unit just isn’t enough of a sample to draw concrete conclusions.  But Popovich knows the limits of his personnel better than anyone, and the fact he’s been unwilling to try other downsized combinations might mean he realizes they won’t work.  The Warriors don’t have a lot on their side in this series on the surface; coaxing the unknown and uncomfortable from San Antonio might be their best way to an upset, and Barnes is the influence that could do it.

*Statistical support for this piece provided by NBA.com and hoopdata.com.

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