The power forward scored 17 points as the team came from behind in the fourth quarter.
The 37-year-old told reporters: "It was our defense. We finally got some stops, followed by boards, and turned them into offense.
"We were getting stops, we weren't getting rebounds or we were getting stops and rebounds, but we weren't making shots, and we had a stretch where we put all three together. It changed everything for us."
The Spurs play the Phoenix Suns later today.