The majors' leading hitter walked off the field with athletic trainer Jamie Reed while the Twins made a pitching change. He said after the game that as soon as he came out of the batter's box in his final at-bat, he felt his SI (sacroiliac) joint -- located in the lower back just above the glute -- "lock up" on him.
"I came in and got it adjusted and it felt better," Hamilton said. "It shouldn't be a problem.
Hamilton had singled to right field against Randy Flores with one out in the eighth. Twins manager Ron Gardenhire put right-hander Matt Capps in to face Nelson Cruz, and while Capps was warming up, Hamilton summoned the trainers.
After a brief conversation, Hamilton was replaced by Cristian Guzman at first base. He is listed as day-to-day.
He was inserted in Friday's lineup at designated hitter after getting a lubricant shot in his right knee. But he said that it felt better before the game.
Hamilton, an AL MVP favorite, is batting .361 with 31 homers and 97 RBIs.