The eighth-seeded Grizzlies have controlled the first-round series of the NBA Western Conference playoff series thus far. On Monday, they took a commanding 3-1 series lead with their 104-86 victory.
Gasol's counterpart, future Hall of Famer Tim Duncan, who was celebrating his 35th birthday, was held to just six points.
"I know a lot of people didn't expect us to be here," Grizzlies guard Mike Conley said. "It's not like we were expected to be up 3-1 at this point. In our locker room, we're just playing it game by game. We want to come into San Antonio looking to end it there. We're focused and want to be able to move onto the next round."
The Spurs now are placing their hopes in making a stand Wednesday night on their home court.
Coach Gregg Popovich pulled his starters with 5:43 left to start resting them for that game.
"They'll need their juice for the next game," Popovich said.
Among those stars is Manu Ginóbili, who missed the first game with an elbow injury. On Monday, the guard scored 14 points.
He was asked if he, Duncan and Tony Parker were feeling old compared to the upstart Grizzlies.
"We've been feeling old for five years. I don't think it's a matter of experience, old or young," Ginobili said. "We're not the most athletic team in the league, and they are tough as we said for a week since we started playing. They are young, athletic. They play hard, and we couldn't find answers in that third quarter."
Parker, meanwhile, said the Spurs, who had 61 wins during the regular season, were feeling the heat.
"Obviously, the whole team is very frustrated," Parker said. "I mean we go through a whole season and get that first seed, and now we're just one game away to be eliminated so it's most important for us to focus on Game 5. That's the most important thing to get Game 5 and try to get another chance to get a win here."
The Spurs got a surprising 10 points from Tiago Splitter, a rookie from Brazil.
The Associated Press contributed to this article.