Josh Hamilton leaves with back issues

MINNEAPOLIS -- Texas Rangers outfielder Josh Hamilton left Friday's 4-3 loss against the Minnesota Twins in the eighth inning with lower back stiffness.

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.

Richard Durrett covers the Rangers for ESPNDallas.com. You can follow him on Twitter or leave a question for his weekly mailbag. Information from The Associated Press was used in this report.