Ohtani, who underwent Tommy John surgery in October 2018, was still working his way back from the procedure in March before the coronavirus pandemic shut down spring training, delaying the start of the season by almost four months.
"I'm sure if I was able to spend the regular, normal rehab schedule, the results might have been different," the 26-year-old said, according to Beth Harris of The Associated Press.
Ohtani authored a 37.80 ERA after recording only five outs over his two appearances on the mound this season. He was diagnosed with a forearm strain in early August and didn't pitch again.
The 2018 AL Rookie of the Year didn't fare much better as a designated hitter, slashing .190/.291/.366 with seven home runs across 44 games.
Ohtani said not being able to watch video of his at-bats during games threw him off.
"I want to know where the pitch was and where I took it," he said. "Ideally, I would have liked to see the replays again. I think it would have helped me."