Detroit Tigers second baseman Hao-Yu Lee, a 21-year-old prospect acquired at last year's trade deadline, has been placed on the injured list with lumbar spine inflammation and could be sidelined for the remainder of the 2024 season.

Lee suffered the lower back injury Aug. 15, while hitting in a game.

He hasn't participated in any baseball activities since the injury.

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Lee, who turns 22 in early February, has spent the entire season with Double-A Erie. The SeaWolves play their final game of the regular season Sept. 15, but they're already locked in for the Eastern League playoffs, meaning they might keep playing until late September.

In 2024, Lee is hitting .298 with 12 home runs, 33 walks and 69 strikeouts across 87 games in Double-A. He had the best month of his season in June, hitting .385 with five homers and a 1.131 OPS.

Lee is above-average in practically every metric on offense, but he isn't elite at anything.

He projects to be an average MLB hitter.

The Tigers acquired Lee, a right-handed hitter, from the Philadelphia Phillies, in exchange for right-hander Michael Lorenzen, at the trade deadline in August 2023. He has experience at second base, third base and shortstop throughout his minor-league career, but he is expected to be a second baseman into the future.

Lee ranks as the Tigers' No. 8 prospect, according to MLB Pipeline.

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Matt Manning throws bullpens

Triple-A Toledo right-hander Matt Manning (right lat strain) is throwing bullpens twice a week. The Tigers hope the 26-year-old can return to Toledo before the Mud Hens' regular season ends Aug. 22, but it's shaping up as a photo finish.

Either way, Manning should be available to help the Tigers down the stretch, if needed.

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Manning hasn't pitched in a game since July 14, the final of eight starts in a row with Toledo. After that start, he reported the right lat injury to the Tigers over the All-Star break.

In 2024, Manning has a 4.53 ERA with 22 walks and 60 strikeouts across 59⅔ innings for the Mud Hens. He also posted a 4.88 ERA with 12 walks and 23 strikeouts across 27⅔ innings with the Tigers.

He has a 4.43 ERA in his four-year MLB career, spanning 50 starts.

Trei Cruz undergoes elbow surgery

Double-A Erie shortstop Trei Cruz, who also plays center field, underwent Tommy John surgery with an internal brace to repair the ulnar collateral ligament in his right elbow.

The 26-year-old injured his right elbow Aug. 15 while throwing during pregame warmups.

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In 2024, Cruz hit .260 with nine home runs, 49 walks and 112 strikeouts in 102 games in Double-A. It was his second full season in a row at the Double-A level.

The Tigers selected Cruz in the third round, at No. 73 overall, in the 2020 draft.

Wilmer Flores begins rehab assignment

Triple-A Toledo right-handed reliever Wilmer Flores (right shoulder stress reaction) continued his rehab assignment Tuesday with High-A West Michigan. He previously pitched in two games for Low-A Lakeland, which were his first games since May 12.

He has thrown four innings in three games during his rehab assignment, including one inning on 21 pitches in Tuesday's relief appearance with the Whitecaps.

Flores posted a 6.04 ERA with 19 walks and 19 strikeouts across 22⅓ innings in 13 games with the Mud Hens before suffering the shoulder injury. He should be able to return to Toledo's bullpen before the season ends Aug. 22.

Both Flores and Manning are members of the Tigers' 40-man roster.

Contact Evan Petzold at epetzold@freepress.com or follow him @EvanPetzold.

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This article originally appeared on Detroit Free Press: Detroit Tigers prospect Hao-Yu Lee lands on IL with back inflammation