SCOTTSDALE, Ariz. -- Luis Perdomo made his Padres debut on Opening Day 2016 after being taken in the previous year's Rule 5 Draft. At the time, he had never before pitched above Class A Advanced.
All things considered, Perdomo held his own nicely that year, posting a 4.30 second-half ERA when he would've otherwise been pitching in Double-A. But the 24-year-old right-hander didn't make much progress in Year 2, leaving 2018 as a critical season for his development.
Perdomo is in a fight for a rotation spot this spring, and he didn't exactly put his best foot forward Sunday in a 5-4 Cactus League defeat to San Francisco. He allowed five first-inning runs before settling in for two scoreless frames. In his manager's eyes, Perdomo may have been a bit overaggressive early on.
"For me, he's young, he's still learning," manager Andy Green said. "He's got two years in the big leagues now, but he's still a very young pitcher. Today I'd rather see that side of the mistakes than take pitches off. He'll learn and grow from it."
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When camp began, Green gave Perdomo "a leg up" in the rotation race, given his upside and the chance he could factor into the club's future. But Perdomo hasn't locked up anything yet.
Clayton Richard and Bryan Mitchell are in the club's Opening Day rotation, and Dinelson Lamet is a heavy favorite to land there. That could leave Perdomo, Christopher Young, Tyson Ross, Robbie Erlin and Jordan Lyles fighting for two spots.
"We're definitely pushing him to make strides [this year]," Green said of Perdomo. "He's competing for a rotation spot. I think he'll adjust and come back from this one pretty well."
Jankowski, Cordero battling for one spot?
Travis Jankowski and Franchy Cordero boast similar skill sets. They're both left-handed hitters who can play all three outfield spots, and they're both threats with their speed and defense. That redundancy might keep one of them off the roster.
"Right now, it wouldn't make a ton of sense to carry both those guys, not that you don't believe in both of their futures," Green said. "I don't go into the season expecting both of them to be on the club. They're fighting for a spot."

As it stands, William Myers, Manuel Margot and Jose Pirela are roster locks. The Padres are likely to carry five outfielders, leaving Jankowski, Cordero, Hunter Renfroe and Matthew Szczur to fight for those final two places.
"The competition is great in the fact that all seven of us can play in the big leagues," Jankowski said. "It drives us. If I see Franchy working hard, I want to be working harder than him. ... We're competing with each other as hard as we can, but in the locker room, we're hugging each other, rooting for each other at the same time."
Schedule unkind to Richard
The Padres have their first off-day of Spring Training on Wednesday and their second on March 19. Coincidentally, those are both dates on which Clayton Richard is slated to pitch.
Green called the schedule "annoying from a planning perspective," before noting that Richard will make two starts on a Peoria back field while the rest of the Major League club is off.
It was also pointed out to Green that those dates line up with Richard starting Opening Day -- and that he hasn't yet named a starter for March 29 against Milwaukee. So how many times, exactly, will Richard pitch on his current every-five-days progression?
"At least the next couple," Green said coyly.

Camp battles
• Young was excellent over four scoreless innings Sunday, recording five strikeouts in the process. The veteran right-hander entered camp as an outside candidate but has thrown his name squarely into the rotation mix, having posted a 2.45 ERA in four Cactus League appearances. Even if he misses out, it's a strong possibility he's at least earning a place as a long man in the Padres' pen.
• The Padres are still learning what they have in Pirela as a second baseman (and figuring out how often he'll play there). Sunday was a bit of an adventure for Pirela, but he managed to boot one ground ball straight to first baseman Eric Hosmer for an out.

Injury updates
• Christian Villanueva sustained a cut on his left (non-throwing) arm, which held him out of action Saturday. He went through Sunday's workout and is expected to return on Monday.
• Right-hander Colin Rea has no timetable to resume throwing, said Green. Rea has been shut down since early March due to a lat strain in his right shoulder.
Up next: Mitchell starts Monday when the Padres head to Surprise to face the Royals at 12:05 p.m. PT. Ross will follow Mitchell, looking to stake his claim to one of those available rotation spots. The Padres will have an exclusive audio webcast of the game.