Buxton was hurt on a last-second slide into second base after the Red Sox had misplayed his pop fly to shallow left field to lead off the game.
"Obviously, he was feeling some real discomfort,'' Baldelli said. "He plays through a lot. He's a tough guy and he always wants to be on the field. I think in this instance, he knew it was something he was not going to be able to play today with.''
Speaking after Minnesota's 8-4 win, Baldelli said he'd hold off on making any roster moves until the results of the MRI came back to the team.
"We're not gonna go there yet. We're gonna wait and see what we find out," Baldelli said.
Buxton signed a seven-year, $100 million extension with Minnesota in November, despite a checkered injury past.
Since he made his major league debut on June 14, 2015, he has played in just 500 of the Twins' 978 games and has been on the injured list 11 times in his career.