GOODYEAR, Ariz. -- Shane Bieber, Zach Plesac and Aaron Civale have locked themselves in as the core of the Indians’ rotation. While Triston McKenzie seems to be the clear choice to be the Tribe’s fourth starter, the last spot won’t be as simple to fill.

Cal Quantrill may be the early favorite to round out the starting crew -- especially after tossing two scoreless innings in Sunday's Cactus League opener -- but other starters, including Logan Allen, have already proven that the battle is just beginning.

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“I’m gonna be a little surprised if [Allen] doesn’t make some noise this spring,” Indians manager Terry Francona said. “I think he’s positioned himself where he’s situated himself for success.”

Allen impressed in the Tribe’s two-and-a-half-inning intrasquad scrimmage Saturday, giving up one run on one hit (a homer by Owen Miller). But what did the left-hander do to position himself for success in 2021? It started by switching to a keto diet last July and receiving guidance from Cleveland’s strength staff.

“Oh my gosh. Doughnuts. One thousand percent doughnuts,” Allen said, when asked which food he misses eating the most. “I’m a coffee and donut fiend, so that was like probably my toughest thing. … When I was coming through the Minor Leagues, younger, you don’t pay attention to those kinds of things as much. You eat fast food all the time.”

But changing his diet was just the beginning. Allen spent the entire offseason at the Indians’ Spring Training facility, learning about pitching analytics, body awareness and everything that promotes better deliveries. Or as Allen described as, buying into the “Cleveland Indians’ pitching factory.”

“My mechanics were definitely flawed, even coming from San Diego and long before that,” Allen said. “Makes you wonder how I got to the place I did, with San Diego and then being fortunate enough to come over here. … In San Diego, I had flashes of good analytics, but I never repeated it. So now it’s to the point where all four of my pitches have lined up very well. The new slider has been pretty unbelievable up to this point.”

“Everything’s more crisp,” Francona said. “His delivery, he’s able to repeat it more because his weight, he’s gotten himself in much better shape. … A lot of times, you see these kids who, sometimes they figure it out on the next team, which you don’t want that to happen. We want him to figure it out here for Cleveland.”

Allen pitched in three games for the Tribe last season, following one appearance in 2019 after he was traded from San Diego at the Trade Deadline, but he has yet to make a start for Cleveland. Despite working 10 2/3 innings in relief (pitching to a 3.38 ERA) for the Indians in 2020, he won’t be evaluated as a reliever during Spring Training.

“I think he’s a starter,” Francona said. “I think in fairness to him, he needs to be a starter.”

Not only are there a handful of options for the club’s No. 5 starter (with the favorites being Allen, Quantrill and Adam Plutko), but every potential starter is 26 years old or younger except for the 29-year-old Plutko. Because everyone is so similar in age, many of the hurlers have said that it’s pushed them to work even harder, and Allen was no exception.

“Just this offseason, I’ve taken leaps and bounds beyond the confidence I had in my ability,” Allen said. “It made me even more confident. It’s gotten me even more excited, being around [Shane Bieber] and all these other guys and seeing they’ve gone through a lot of the same things.

“I haven’t been this excited to play baseball in a very, very long time.”