Texas Rangers rookie Evan Carter likely will miss the rest of the regular season because of a lumbar sprain in his back that has limited the outfielder to 45 games.

A big part of the Rangers’ World Series title run last year, Carter hasn’t played since May 26. He had several setbacks when trying to ramp up his hitting progression.

General manager Chris Young said Tuesday that Carter has seen several specialists in the past week who determined the 21-year-old needs a lengthy period of rest without rotational activity in his back.

“I’m not overly optimistic that we’re going to see Evan again in the regular season,” Young said. “It’s going to take some time and we want to protect him. He’s a huge part of our future.”

Carter is hitting .188 with five homers and 15 RBIs. He batted .053 (2 for 38) with one RBI in his last 14 games during a stretch when he sat out a week without initially going on the injured list.

Texas put him on the 10-day IL on May 28 and transferred him to the 60-day IL on Monday.

“What I understand from the experts that Evan has seen, that it’s not a long-term concern,” Young said. “We just haven’t given it enough time to heal, and we’ve got to step back and give him the time that he deserves, that he needs, and Evan will be fine moving forward.”

Young said Carter is already on a core program of exercises and stretches to protect his back. But he is not swinging a bat because of the twists and torque needed to do that.

After his call-up last September as an injury fill-in, Carter made his big league debut 10 days after his 21st birthday and hit .306 with five homers and 12 RBIs in 23 games. He reached base in all 17 of the Rangers’ postseason games, hitting .300 with an postseason record nine doubles. He also had 10 walks.

He went into this season considered a top candidate for AL Rookie of the Year, still qualifying after accruing only 62 at-bats and 24 days of big league service. He had almost as many at-bats (60) in the postseason.

Reporting by The Associated Press.

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