Spring training is here and the A's starting rotation is still a question mark. But, two pitchers who can play major roles later this year made big strides to open camp.

Prospect A.J. Puk and 27-year-old Jharel Cotton threw off a mound at full distance for the first time on Tuesday since the two underwent Tommy John surgery before the 2018 season.

What a nice sight to see, Jharel Cotton and AJ Puk throwing off the mound with everyone else: pic.twitter.com/YscZd9rkfU — Susan Slusser (@susanslusser) February 12, 2019

Cotton said throwing off a mound at 60 feet and six inches was "like Christmas."

“It felt great, my first bullpen at 60 feet, 6 inches,” Cotton said to reporters. “It was kind of fun, I was beside Puk and we were doing the same thing. We were kind of excited about it and getting after it. ... It’s been such a long time. We felt like kids again.”

The two threw at 70 percent effort level, hitting between 70 and 76 mph on the radar gun. Cotton and Puk both missed all of last season, but should be factors in Oakland by midseason.

In 2016, Cotton made his MLB debut and showed his promise by posting a 2.15 ERA over five starts. He then struggled in 2017, going 9-10 with a 5.58 ERA over 24 starts.

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Puk is the A's top pitching prospect behind Jesus Luzardo. He was their top pick in the 2016 MLB Draft and has a 3.82 ERA in his minor league career with 184 strikeouts in 125 innings pitched.

The 6-foot-7 left-hander said his arm "felt amazing" in the bullpen.

Though the A's will monitor both arms closely, keep an eye on their progress this spring as they get closer to actual game action in the next few months.