PEORIA, Ariz. -- The first five months of Cal Quantrill's 2019 season couldn't have gone much smoother. The right-hander earned his big league callup in May, and by June, he was a serviceable weapon who could pitch in practically any role.

In early July, Quantrill was handed a starting job, and he quickly established himself as one of the most reliable pitchers in the rotation. His ERA dipped to 3.32 by late August, as he began to entrench himself in San Diego's short- and long-term rotation plans.

Then, his season went off the rails. Quantrill allowed eight runs in three consecutive starts, and he finished with a 12.05 ERA over his final five outings. A largely successful rookie season instead culminated with a 5.16 ERA and five straight losses.

"A baseball season is 162 games, and I think I was really good and proved I belonged through about 140 of them," said Quantrill, who pitched a simulated game at the Peoria Sports Complex on Monday. "I wore out at the end. That's not good enough. That was a pretty disappointing month.

"But I tried to take the good from last season. I can dominate at this level. I did for a lot longer than I struggled."

Lesson learned, Quantrill says. If anything, his September struggles served as motivation for 2020. He spent his entire offseason in San Diego working out at the team's facilities.

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Quantrill, 25, entered camp on the fringe of both the rotation and bullpen races. There are two places available in the rotation, though Zach Davies and Joey Lucchesi are the early favorites. In the bullpen there's, at most, one job available.

But if the Padres get the version of Quantrill they got last July and August, there’s room for him somewhere on the roster. Quantrill, to his credit, said he doesn't mind battling for his job.

"It means that the Padres are in a good spot, the fact that we're talking about real battles for spots in the rotation, in the ’pen," he said. "It means we've taken a huge step forward. ... I'm excited about it."

Quantrill faced six hitters Monday during a simulated game. He allowed a double down the line to Jake Cronenworth and induced a trio of popups and a pair of ground balls. If the Padres stay on their normal throwing progression, Quantrill could be lined up to pitch the Padres’ Cactus League opener Saturday against Seattle, though manager Jayce Tingler has yet to name any probable pitchers.

Quantrill says he isn't picky about his role, but it's clear that both he and the Padres believe he's best suited as a starter. He will be built up that way this spring, but if circumstances change, Quantrill has already proven himself capable of adapting.

"Pitching is pitching," Quantrill says.

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Perhaps the best argument for Quantrill as a starter is the evolution of his slider. In the Minors, he relied heavily on his fastball/changeup mix. But his slider was arguably his best weapon last season.

Quantrill now has three Major League-caliber pitches (and he even mixed in a curveball or two on Monday). The cerebral right-hander also has a season’s worth of big league experience throwing those pitches, which helped in his preparation for this season.

"When you're in the Minor Leagues and you go into an offseason, sometimes you can be at a little bit of a loss," Quantrill said. "You wonder, 'What is it that I need to do to take the next step?' You've never even seen a big league hitter hit against you, so you don't know exactly what it is you need to improve.

"This offseason, I had a very good idea of what I needed to be better at this season. And I got to work on those things."

Noteworthy
• The full contingent of Padres position players reported to camp on Monday, though their first full workout isn't scheduled until Tuesday morning. Tingler will address the team for the first time before the workout.

• Garrett Richards, Craig Stammen and Matt Strahm were among the pitchers who faced hitters during live batting practice on Monday. Closer Kirby Yates threw a bullpen session.