82Games.com has put together a set of statistical defensive rankings for players:
http://www.82games.com/nichols1.htm
It's an interesting technique. The results for the Spurs (including positional rank which I added, based off the final DCS Rating) are:
Player Team Pos Box Def.
Rank +/-
barry,brent san SG 82 5.8
bonner,matt san PF 195 5.7
bowen,bruce san SF 197 -9.6
duncan,tim san C 30 -6.5
elson,francisco san C 134 0.3
finley,michael san SG 214 7.3
ginobili,manu san SG 16 -4.7
horry,robert san PF 11 -4
oberto,fabricio san C 288 3
parker,tony san PG 164 -1.2
udrih,beno san PG 285 5.2
vaughn,jacque san PG 273 -3.3
Player +/- Drtg Drtg DCS Positional Rank
Rank Rank Rating
barry,brent 314 102 36 60 21
bonner,matt 313 100 21 42 50
bowen,bruce 1 103 57 84 8
duncan,tim 13 94 2 100 1
elson,francisco 167 97 5 78 23
finley,michael 321 103 57 29 40
ginobili,manu 27 98 7 99 1
horry,robert 43 98 7 98 4
oberto,fabricio 268 100 21 33 46
parker,tony 109 102 36 77 9
udrih,beno 304 103 57 20 58
vaughn,jacque 64 102 36 66 17
The system says we have the best defensive C in the game, using TD as C. We also have the best defensive SG with Manu. Horry is the 4th best defensive PF in the game, Bruce is the 8th best defensive SF in the game, and Tony is 9th of the PGs. Beno is the worst defender on the team, both by overall score, and relative to his position... It also produces some interesting results, like Barry being a better defender than Finley.
It's also interesting to note, that we only have 4 players who are below average relative to the league (DCS rating < 50), Matt Bonner, Beno Udrih, Micheal Finley and Fabricio Oberto.