The Milwaukee Brewers' bullpen might have just taken a big hit.
After experiencing discomfort following his last outing Sunday, Corey Knebel will have his right elbow examined by a specialist Thursday in Arizona.
Manager Craig Counsell revealed that Knebel has an issue with the ulnar collateral ligament in his throwing elbow, according to Robert Murray of The Athletic. A UCL injury can often be a precursor to Tommy John surgery.
"There is reason for concern," Counsell said, according to Murray.
Counsell did note that Knebel didn't suffer a complete tear of his UCL, and suggested it's not a new problem. However, it has apparently been deemed severe enough that he's now seeking a second opinion.
"Corey has pitched with this for a long time, so we've got to figure out what's there, what's new," Counsell said, per Adam McCalvy of MLB.com. "We're going to make sure we get the right answer and then move forward."
Knebel has been an integral part of Milwaukee's bullpen over the past two seasons, saving 57 games and striking out 214 hitters in 131 1/3 innings for the Brewers since 2017.
The 27-year-old right-hander also pitched well during last year's postseason run, allowing one run in 10 innings while striking out 14.
Milwaukee's daunting bullpen - which combined for MLB's fifth-lowest ERA in 2018 - is already expected to enter the regular season without closer Jeremy Jeffress as he recovers from a sore right shoulder. Bobby Wahl is also out for the entire 2019 campaign because of ACL surgery.