Game 1
MEM - 37/67 (55.2%)
Assists - 22
SA - 28/70 (40%)
Assists 13
Game 2
MEM - 35/88 (39.8%)
Assists - 17
SA - 32/73 (43.8%)
Assists - 21
So, I believe this has a lot to do with Manu. The Spurs had an assist on 46% of their FGs in Game 1, as opposed to memphis' 59%. But tonight, it was 65%-48% in favor of SA. This is either due to Manu returning (we all know how he helps others get easy shots, gives the team energy, etc) or just the team caring more tonight.
Also, the Grizzlies had 21 more shot attempts tonight than they did Sunday. But the Spurs won both rebound battles. I couldn't find the offensive board stats, but did the Grizzlies really win them by that much?