Ginobili sparked the Spurs to a nine-point lead in the fourth quarter and drew the foul that negated Carmelo Anthony's winning basket in San Antonio's escape Thursday night.
"I knew Carmelo was going to attack the rim," Ginobili said. "We were not going to let him take that open shot. Antonio [McDyess] made him a driver, and I was in the right position. It's my job to be there and try to draw a charge. When he jumped, I knew I was going to get it because I was right outside the circle.
"I definitely didn't want to make any doubts for the refs. A guy that explosive, it's hard to stop and pull up. I knew I was right out of the circle and he got me right in the chest."
Anthony, who led Denver with 31 points, thought he had the game-winning play, not Ginobili.
"No, obviously what I think and what they called are two different things. I thought I made a great play. I took advantage of how Richard [Jefferson] was guarding, attacked. I don't think I could've got a better look at it than that," Anthony said.
"It's tough, you know, just going out there playing as hard as we played out there and to lose the game on something like that."
The bizarre end capped a frenetic finish in which the Nuggets erased a nine-point deficit with 6 minutes left.
The Spurs led 111-108 with 8 seconds to go when Anthony got behind the defense for a dunk. McDyess' inbounds pass was deflected by J.R. Smith off Ginobili's head and into the arms of Anthony, whose basket gave the Nuggets a 112-111 lead with 7.1 seconds left.
Ginobili's running bank shot at 4.2 seconds put the Spurs back on top 113-112.
After a timeout, Anthony got the inbounds pass from Ty Lawson and drove the lane past Jefferson, but Ginobili slid over and drew the foul as Anthony's shot fluttered through the net at the buzzer and the crowd went crazy.
Official Haywoode Workman waved off the basket for an offensive foul.
Nuggets coach George Karl was crestfallen over the call.
"It's a play that I think goes either way a lot," Karl said. "It seemed like the referees, they like to hit us with tough calls. It was a tough call. Good play. Good basketball. Melo made a great play. It's close. I've seen it called both ways."
But at the buzzer?
Told that TV analyst Scott Hastings said he hadn't seen that in his nearly three decades watching NBA basketball, Karl said, "I'd probably agree with Scott."
Spurs coach Gregg Popovich said: "I never even saw it. I just saw Carmelo barreling to the rim and I'm thinking, 'Oh my god.'"
After a review, the officials put 0.4 seconds back on the clock, and the Spurs inbounded the ball for the win.
It was the second game-winning play in two nights for Ginobili, who hit a fallaway jumper as time expired Wednesday, lifting San Antonio over Milwaukee 92-90.
"He's a stud," Popovich said. "He's been a competitor, he's won championships here and overseas, and he's been MVPs of things. He scored the two free throws down the stretch, then he scored the winning bucket and then he took the charge. That pretty much says it all about what he's capable of doing."
San Antonio improved to an NBA-best 22-4 while dropping the Nuggets to just their second loss in 13 home games.
Averaging 20.2 points, Ginobili had just three points when he sliced in for a backdoor basket, hit a step-back basket -- like the one he used to beat Milwaukee -- and then hit a deep 3-pointer to give the Spurs a 94-88 lead early in the fourth quarter.
Until the final minute, the highlight of the game was Smith's dunk over Gary Neal with 0.6 seconds left in the first quarter. His subsequent free throw gave the Nuggets a 37-28 lead that marked the most points the Spurs had allowed in any quarter this season.
Smith took off 11 feet from the basket and slammed it through the hoop with both hands as he ran into Neal, sending him to the court. The rim-rattler drew nods of appreciation from the Nuggets bench and was posted on YouTube within minutes.
Denver PG Chauncey Billups (wrist) missed his second straight game. The Nuggets hope he can return Saturday night against Minnesota. ... Spurs C DeJuan Blair returned from hyperextending his right knee Wednesday night against Milwaukee to log 14 minutes.