The Dominican slugger paid little attention to a bruise he got Thursday on his left ankle.
"Right now, I don't feel completely recovered, but at least, 75 percent in shape," Pujols told ESPNdeportes.com before the Cardinals' game in Miami.
"Pain is part of the game, and you have to learn to deal with that, especially when you get it at the beginning of the season."
Pujols, last year's National League MVP, was named April's player of the month after hitting .346 and setting a major-league record with 14 home runs in the month. He also set a team record with 32 RBI in April.
However, early last week, Pujols injured himself during a defensive play in the series against Chicago Cubs.
Pujols has had light electroshock treatments, massages and a dose of antibiotics to ease his back pains.
"I've never had back trouble before, and only now I know how difficult it is to deal with these kinds of injuries. It is especially hard to swing," said Pujols, who has one home run and one RBI in his first three games in May.
"My ankle injury isn't significant," he added.
In spite of his mini-slump, Pujols' numbers this season are extraordinary. The slugger is batting .315 and leads the league in home runs (15) slugging (.848), and on-base percentage (.475).
He also ranks second in the NL in RBI (33) and walks (29).
Pujols has virtually carried St. Louis (17-12), which sits in third place in the Central Division, behind Cincinnati and Houston.
Beyond Pujols' injury problems, oufielder Larry Bigbie hasn't been able to play this season, and third baseman Scott Rolen and center fielder Jim Edmonds have been playing through ailments as well. Left-handed reliever Ricardo Rincon was placed in the disabled list, and starter Mark Mulder has had recent back problems.
"The most important thing is to help the team, no matter how much you have to strain yourself to achieve it," Pujol said.