LAKELAND, Fla. -- Daniel Norris might have the most promising arm in Tigers camp this Spring Training. His back, however, could keep him from breaking camp in Detroit's rotation.
For the second time in four days, a lower-back issue has scratched or halted Norris from a scheduled outing. This time, he had to leave Tuesday's 16-1 loss to the Blue Jays after 25 pitches and six batters.
The Tigers classified Norris' injury as lower-back tightness.
"It seems to be [a recurrence], pending test results," manager Brad Ausmus said.
Even if tests show Norris is fine, he faces the challenge of building up his pitch count to regular-season readiness with just two starts left.
Asked if this affects Norris' chances of cracking the rotation, Ausmus was honest.
"It doesn't help them," Ausmus said, "even just from a pitch-count perspective."
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Norris pitched on Tuesday against his old club because he was scratched from his previously scheduled outing on Saturday with the same injury. He felt fine early on Tuesday before the issue flared up again.
The 22-year-old southpaw retired the first batter he faced, but none of the next five. Jose Bautista battled Norris for nine pitches, fouling off four consecutive two-strike pitches, before taking a fastball just off the plate and another one inside for a walk. That sequence might have been where Norris aggravated his back.
"Actually, his velocity was real strong for his first 10 pitches," Ausmus said, "and then you could tell he didn't feel quite right. He said it tightened up as it went."
Four pitches later, Troy Tulowitzki jumped a fastball for a three-run homer. Norris didn't turn to watch its path to the left-field berm, possibly not so much out of frustration but out of physical aggravation.
Norris gave up a Chris Colabello double after Tulowitzki's homer, then fell behind 3-0 to Justin Smoak. Ausmus and head athletic trainer Kevin Rand visited Norris, who was then pulled from the game after recording just one out and facing six batters. Norris walked gingerly with Rand straight to the Tigers' clubhouse in the right-field corner.
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Acquired from Toronto in the David Price trade last July, Norris is competing with Shane Greene, Matt Boyd and Buck Farmer for a spot in Detroit's rotation. While his repertoire has shown glimpses of last year's form, his results have been inconsistent, creating opportunities for Greene and Boyd to capitalize on strong springs.
Norris has allowed seven runs on 12 hits over 6 1/3 innings with four walks and eight strikeouts. Greene has given up four runs on 13 hits over 13 2/3 innings with three walks and 14 strikeouts. Boyd has yielded five runs on 12 hits over 13 2/3 innings with three walks and 13 strikeouts.
Ausmus has emphasized that Spring Training results won't determine the fifth starter, saying the decision comes down to "who we think can perform the best."
"In terms of performance, it's probably been Boyd and Greene so far," Ausmus said on Tuesday morning. "They're probably pretty close. But I didn't say who performed the best. I said who we thought could perform the best."
Ausmus was hoping Norris would take a step forward Tuesday. Instead, the recurring back issues have created another question. 
Fellow starter Anibal Sanchez began game action on Monday after nearly a month out with triceps inflammation and later a bronchial illness. Reliever Alex Wilson has yet to pitch in game due to a lat strain behind his shoulder. Victor Martinez has missed the past week with a left hamstring strain and appears limited to pinch-hitting duties at best for the season-opening series at Miami. Cameron Maybin, meanwhile, won't be ready for Opening Day as he heals from a fractured left wrist.