Lakeland, Fla. — The Tigers’ 4-3 spring loss to a Blue Jays split-squad team produced more encouraging signs than worrisome ones.

Start with the good news:

■ Right-hander Jordan Zimmermann went 5⅓ strong innings and threw 88 pitches.

Although there wasn’t a high level of concern, the Tigers were eager to see this type of performance after he was KO’d in the first inning of his last Grapefruit League start and made his last start on the back fields against minor-league hitters.

“I wasn’t worried about him because his stuff was good,” manager Brad Ausmus said. “Stuff plays in the long-term, even if it doesn’t in the short-term. But he did pitch well today.”

BOX SCORE: Blue Jays 4, Tigers 3

He pitched into the sixth inning, allowing one run and two hits. Sixty-two of his 88 pitches were strikes. His fastball was clocking at 92-94 mph and he mixed his slider and change-up proficiently.

“I caught him early in spring and now and he’s been good,” catcher Alex Avila said. “I know he had a couple of rough outings in the middle, but the times I’ve caught him, his stuff’s been right there.

“He’s been working on his command, but he’s always been a guy with good command. Today, there were times when he would lose command on his slider, but he’d regain it. In time, in a few starts, he will get a better feel for that.”

He had two stressful innings. He walked and hit a batter in the third, then got a key strikeout of Ezequiel Carrera. He gave up a single and double to start the fourth and skillfully minimized the damage.

He struck out Darrell Ceciliani with a high fastball, gave up a sacrifice fly to Ryan McBroom and ended the inning with a fly out by Jake Elmore.

“The last couple outings I’d be a little quick and then a little slow (with his delivery),” Zimmermann said. “Today I felt like I was where I needed to be and got a lot better results. I was able to get six up-and-downs, all my pitches were working, the change-up was good — I’m happy.”

He used words like awesome and amazing to describe his health — that alone is a triumph considering his neck and shoulder issues last season.

“I’m just excited to get out there under the lights and play a meaningful game,” he said.

Zimmermann is expected to start in either the second or third game of the season against the White Sox in Chicago.

“They haven’t told me,” he said. “I don’t even know if I’ve made the team.”

This just in: Zimmermann has made the team.

■ The battle for the fifth rotation spot is now a two-man race between Matthew Boyd and Anibal Sanchez.

Mike Pelfrey, for the second straight outing, worked one inning in relief. He is no longer being stretched out as a starting pitcher.

Ausmus wouldn’t declare him out of the race, but he said, “The other two have pitched extremely well.”

Pelfrey has gotten the message.

“I feel like I’ve made some changes this spring, changes for the better,” said Pelfrey, who struck out two in a scoreless inning. “The last couple times I’ve been trying to learn a little different role, coming out of the 'pen, different routine.

“Obviously the other two guys have been great. I get it. At the end of the day I’m going to pitch when they tell me to and do my best.”

A bullpen job is not guaranteed, either. He’s battling Blaine Hardy, Daniel Stumpf, Angel Nesbitt and possibly Sanchez if he doesn’t get the starter’s job.

“Start, relieve — you want me to pinch run I’ll do that, too, Pelfrey said. “I don’t care. I just want to play. I want to be on the team. I want to pitch. Whatever they tell me, I’ll do it.”

■ Nick Castellanos’ torrid spring continues.

He cleared the berm in left field with a mammoth shot in the first inning, his fourth homer of the spring, then he laced an opposite-field double off the wall in right in the third. He scored on an RBI single by Miguel Cabrera in the Tigers’ 2-2 spring tie with the Blue Jays split-squad team.

Castellanos came in hitting .367. In the previous 16 games, he hit .365 with eighth doubles and four home runs with 14 RBIs.

Now some mildly worrisome outtakes:

■ The Bruce Rondon mystery continues.

He threw a couple of fastballs at 94-95 mph in his one inning of work Sunday — one of them was lashed onto the berm in left-center field by McBroom. Mostly though, Rondon threw his secondary pitches — slider (83 mph) and change-up (90-91).

“I don’t know if that was by design or not,” Ausmus said. “His velocity is down a bit. But that being said, he could take the mound in the season and throw 99. The velocity being down is somewhat concerning.

“But he did hit 96-97 in the WBC and he hit mid-90s early in the inning today.”

■ Francisco Rodriguez is having another very typical spring.

Which is not always a fun thing to witness. Rodriguez, the game’s active save leader and third all-time, uses spring training to get his arm, body and pitches in shape. He worries nothing about results.

So, he won’t stress the two home runs he gave up to minor-league hitters in the ninth inning Sunday (Alex Monsalve and Christian Lopes). Neither will the Tigers.

The only mildly worrisome part is he’s been away from camp so long (at the WBC) and the Tigers staff haven't had much time with him. It was just his second spring outing, not counting his work on the back fields.

Twitter @cmccosky