MESA, Ariz. -- Frankie Montas had a plan to enter Spring Training ahead of most A’s starters by following a rigorous throwing program throughout the winter. But after he tested positive for COVID-19, the progress made from all that offseason work was derailed.

Missing the first week of camp, Montas experienced mild symptoms of the virus, such as body aches and headaches, but no fever or loss of taste or smell. Quarantined in his home in Arizona for 14 days, the right-hander said the worst part of the whole ordeal was not being able to hold his son and 5-month-old daughter for two weeks.

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Now back with the club, the 27-year-old said he is still experiencing light congestion in his chest, though he is able to get through his workouts without issue.

“I feel good now. I’m trying to get my body back in shape and get ready to go,” Montas said. “Before I had COVID, I was throwing live bullpens. It’s not going to take me that long to get back in pitching shape.”

Coming off an inconsistent 2020 campaign in which he thrived with a 1.57 ERA through his first four starts of the regular season before posting with an 8.70 ERA over his final seven outings, Montas has a few things he wants to get back to that escaped him last year.

Topping the list: Having fun again. Known for carrying a smile to the mound, that grin disappeared as he went through his struggles in September.

“I’m trying to compete, do my job and have fun. Enjoy the game,” Montas said. “I feel like last year I wasn’t having as much fun as I usually do. This year, my goal is to just attack the hitters every outing and try to help my team as much as I can.”

One way Montas can have more fun back is by reviving his splitter. It’s the pitch that led to a breakout season in 2019. He went 9-2 with a 2.63 ERA across 16 starts. That season, Statcast tracking shows, Montas threw the splitter 18.2% of the time, which was about as much as he threw his four-seam fastball.

Last year, Montas decreased the usage of his splitter to 12.9%, making it the least thrown of his four pitches.

“I feel like I was more focused on throwing my two-seamer,” Montas said. “When I have that good splitter in my back pocket, why not use it more? I feel like in ’19, that was the key. I was using all my pitches. Last year, I was more just fastball and slider than anything and forgot about the splitter. But that’s one of my best pitches.”

Though he was Oakland’s Opening Day starter last season, Montas is not taking his spot on this year’s club for granted. The A’s return all five of their primary starting pitchers from 2020, and the organization’s No. 1 prospect, A.J. Puk, is waiting in the wings. Montas wants to re-establish himself as the ace of a talented staff that features Jesús Luzardo, Chris Bassitt, Sean Manaea and Mike Fiers.

“I feel like that gets me more hungry,” Montas said. “We have a great rotation, so I feel like all of us have to step up our game. Our rotation is one of the best right now, and I don’t want to stay behind. I want to be able to compete with all the guys. Of all five starters, I want to be the one at the top.”