MESA, Ariz. - Right-hander Chris Bassitt knows he’s not high on the A’s radar this spring, and, he said, that’s fair enough.

“Forgotten? Yes, I do feel that,” he said. “At the same time, it’s warranted. But I’ve pretty much made a career of proving people wrong from the aspect of you’re the odd man out and all of a sudden you’re in there. That role, I’m comfortable with it. As for people who say I’m not in one of the five spots, that’s warranted.”

Bassitt is almost two years removed from Tommy John surgery. He has had no pain since the procedure and he believes he can earn a rotation spot.

He’s realistic, though. His 2017 season was erratic after he returned to pitching.

“Last year was so different, because I didn’t know who was showing up to the ballpark from day to day,” he said. “That was the most frustrating thing to me, I didn’t know if it was the guy throwing 93-95 mph or the guy throwing 86-87 and I couldn’t tell until I was out there. It was such a mental battle all year feeling the ups and downs of everything.”

Does he know which guy he is this spring? “Honestly, that’s the million dollar question,” he said. “I don’t. Until games start, I don’t know.”

Bassitt, who had a 3.56 ERA with Oakland in 2015, worked in 24 minor-league games last year and put up a 5.33 ERA. He wasn’t a September callup - instead, he got an extra month of rest. He had mixed feelings about that, but he appreciated how forthright the front office was with him about his status.

“Obviously, it stunk I didn’t get called up,” he said. “At the same time, I totally agreed with it. I wasn’t ready. I needed time off and I think the extra month of rest will pay huge dividends coming into this year.”

Manager Bob Melvin said that it’s unclear if there will be enough innings for Bassitt to get a long look for a starter spot; there will be a healthy competition for the final three spots in the rotation between Daniel Mengden (Melvin gave him the early lead for the No. 3 job based on Mengden’s fine September), Paul Blackburn, Jharel Cotton, Andrew Triggs and Daniel Gossett.

If Bassitt doesn’t wind up with a rotation spot, he’s likely to move into the bullpen, where he could be a long relief option for Oakland.

Susan Slusser is a San Francisco Chronicle staff writer. Email: sslusser@sfchronicle.com Twitter: @susanslusser