ST. LOUIS -- The Cardinals' search for a closer will extend beyond this season as it was determined that Trevor Rosenthal will require Tommy John surgery to repair a partially torn ulnar collateral ligament in his right elbow. Dr. Neal ElAttrache will perform the procedure next week.
The surgery not only ends Rosenthal's season, but it will cost him much -- and possibly all -- of 2018 as well. The timing also complicates his move toward free agency, and it leaves the Cardinals without an obvious answer as to who will fill the ninth-inning void in his absence.
"It certainly creates a need where we previously had a pretty set answer," general manager Michael Girsch said. "In the short term, there's not a ton we can do about it, unfortunately, because of the time of year. We're doing our best. In the longer term, it is something we'll have to add to the things we're trying to address this offseason."

The short-term options are the ones the Cardinals have auditioned since Rosenthal exited an appearance last Wednesday with discomfort in his elbow. Tyler Lyons, who has thrown 13 2/3 consecutive scoreless innings entering Wednesday, and Seunghwan Oh, who opened the season as the team's closer, remain the most likely to get the first crack at seizing the role.
"We'll figure it out as we go," manager Mike Matheny said. "We've got a lot of opportunity for somebody to step in and take over the spot, a few spots. We are going to let everybody see what they can do and see who looks the best to fill that spot."

The outlook for next season is just as complex. If an internal option does not emerge, the Cardinals will be seeking to add a closer via trade or free agency. It'd be an unexpected add to an offseason wish list that already includes an impact middle-of-the-order bat.
"We've got 37 games -- whatever the magic number is -- to see if someone steps up and puts a stamp on the role or not," Girsch said. "I think we're going to be in the market to improve our bullpen, one way or the other. What that looks like sort of depends on what's available."

One possibility would be to re-sign Oh, though his struggles against left-handed batters this season necessitated his move out of the closer's spot earlier in the summer.
That's when Rosenthal, who led the Majors with 93 saves from 2014-15, reclaimed the job. He went on a run during which he allowed one run in 14 appearances before feeling discomfort in his elbow during an Aug. 12 appearance. He tried to pitch again four days later, but the radar gun further affirmed that something was not right.
That prompted a visit with team physician George Paletta, who shared his scans and notes with ElAttrache. The two agreed surgery was the best option.
"It's difficult in the sense of how things were taking shape for me," Rosenthal said. "I was putting a pretty consistent year together [and on] a roll. I was able to help us win games, so to take that away is definitely a bummer."
On the business side, the Cardinals also have to now determine what to do with Rosenthal. He was to be arbitration-eligible for a third time this winter and due for a salary increase from the $6.4 million he's earning in 2017. It's a financial commitment the Cardinals won't want to make for a pitcher who may need the full season to recover from surgery.
The club could choose to not tender Rosenthal a contract and try to re-sign him for a lesser amount, or under a Minor League contract, to retain control of the right-hander.