La Russa, speaking to reporters at the Cardinals' spring training home of Jupiter, Fla., said the Major League Baseball Players Association is using Pujols to "set the bar" higher on salary levels throughout the game, thus putting baseball's best hitter under pressure to hold out for more money.
"I know what he's going through with the union, and to some extent his representatives, because the representatives are getting beat up by the union," La Russa told MLB.com.
"'Set the bar, set the bar,' and that's (expletive), really and truly. You've got to deal with it. It's not the way it should be."
The Cardinals have said Wednesday is the deadline for getting a contract extension deal done with the two-time defending National League home run champion, after which Pujols will concentrate solely on baseball.
Michael Weiner, executive director of the MLBPA, disputed La Russa's claims.
"It's never been the union's policy to pressure players, and certainly it's never been the union's policy to pressure players because they have to set the bar for other players," he told the Web site.