Tommy John surgery sidelines Keaton McKinney for 2017

Arkansas' Keaton McKinney throws a pitch during a game against Texas A&M on Sunday, May 1, 2016, at Baum Stadium in Fayetteville.
Arkansas' Keaton McKinney throws a pitch during a game against Texas A&M on Sunday, May 1, 2016, at Baum Stadium in Fayetteville.

— Arkansas will be without one of its most experienced pitchers in 2017.

Junior right-hander Keaton McKinney will undergo Tommy John surgery on his elbow and will miss the season, Razorbacks coach Dave Van Horn said in a statement Thursday. McKinney, a freshman all-American in 2015, was expected to contend for a weekend starter job this year.

"We expect him to make a full recovery following his surgery and look forward to having him back on the field as soon as he is healthy and ready to return," Van Horn said.

McKinney is eligible for a redshirt season, but it's unclear when he will be able to pitch again. Recovery for Tommy John surgery typically is at least 12 months for pitchers, although the timeline can fluctuate based on the severity of the injury.

McKinney also is draft-eligible this summer. The Ankeny, Iowa, native was listed as one of Baseball America's 80 best prospects in 2014, but wasn't drafted until the 28th round by the New York Mets because of a high asking price to skip college.

When Arkansas opened preseason practice last Friday, Van Horn said he was optimistic McKinney had turned a corner after more than a year of struggling with injuries. McKinney pitched through a hip injury during the Razorbacks' run to the College World Series two years ago and underwent hip surgery shortly after his freshman season when he led the SEC with two complete games, including a shutout at Alabama.

He struggled to recover from the injury, however, and his production dipped as a sophomore when he recorded a 6.66 ERA in 12 starts and a relief appearance.

McKinney struggled during the Razorbacks' early portion of fall practice, too, but Van Horn said he had been encouraged by a couple of bullpen sessions in January.

“(Keaton) threw a couple good innings here and there toward the end of fall ball where you’re going, ‘Wow, that kind of reminds us of the guy we had as a freshman,’ except he is throwing a little bit harder,” Van Horn said last Friday. “He’s a lot bigger, more physical."

It's unclear whether the Tommy John surgery was required because of an injury sustained in practice or was the result of a lingering injury. He had thrown as recently as a scrimmage last Saturday.

"He looks like the old Keaton again," Arkansas sophomore pitcher Blaine Knight said last month. "It's good to see that again because of the struggles, and the ups and downs he went through last year."

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