MESA, Ariz. -- A's right-hander Jharel Cotton is keeping a healthy dose of optimism in his pocket as he heads to Dallas for a second opinion on his injured elbow.
Cotton was diagnosed with a sprained ulnar collateral ligament earlier this week, but isn't yet ready to commit to what typically follows -- Tommy John surgery.
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"I'm trying to be optimistic about it," Cotton said Friday morning. "I don't know anything for certain. I'll see what happens, and hopefully it's better news and we'll go from there."
Cotton, who also has a strained flexor muscle, has plans to see orthopedic surgeon and Rangers head physician Dr. Keith Meister. Tommy John surgery would sideline Cotton for at least a year, which is why he's yearning for a different resolution.
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His optimism partly stems from the improvement he's felt in his arm since exiting his Monday outing after four innings. He struck out five for the third time this spring and appeared well on his way to locking down a rotation spot again.
Cotton, 26, was 9-10 with a 5.58 ERA in 24 starts over two stints during his 2017 rookie season.
"It's tough, because this year I wanted to come out and prove to these guys that I can pitch in the big leagues, and I think I've done everything right to get better for this year," Cotton said. "Now, it's a little setback right now.
"It wasn't one pitch. I don't know when I felt it. I didn't feel no pop, I didn't hear anything. I didn't have any numbing sensation. My elbow has full strength."
Cotton experienced similar discomfort in his elbow in September, but an MRI showed no structural damage.

"That's the thing, I thought it felt the same," he said. "I thought it was the same thing as September. I thought we would get some more treatment or whatever, but it wasn't the same."
He also suffered a stress fracture in the elbow in 2013 and had two screws inserted into the joint, but he believes these injuries to be unrelated.
With Cotton out of the mix for at least several months presumably, an already wobbly A's rotation faces more questions. The pool from which to fill out the starting five has shrunk; right-hander Andrew Triggs will likely be needed in the rotation, which gives the A's one less long-relief option -- a necessity, manager Bob Melvin sees it, should they carry an eight-man bullpen.
That's looking all the more likely, particularly in the wake of Cotton's injury. Melvin would subsequently be left to manage a three-man bench.
"From the very beginning, I thought eight was going to be the number," Melvin said. "We'll see once we get there. Early in the season, you don't want to throw too much at the starters. There's a good chance we'll go with eight, but we haven't committed to it yet. "