Shawn Kelley, a closing candidate to start the season, may now be done for the rest of 2017. (Julie Jacobson/Associated Press)

NEW YORK — Shawn Kelley should be able to feel his fingers. He should not have extreme swelling in his throwing hand — or either hand, really. So what happened to him Friday night, when he left the game abruptly with both problems, signaled trouble.

Kelley does not know exactly what that trouble is yet. He had an MRI on Saturday morning and does know that the ulnar collateral ligament in his elbow is intact. Kelley has had two Tommy John surgeries, so trouble with the UCL would have represented a career-ending injury, not a season-ending one.

“I feel really good that as far as the UCL stuff, the Tommy John stuff, that’s not really an issue,” Kelley said. “It’s trying to diagnose what’s causing the swelling, the tingling, the numbness, and then trying to fix that.”

Manager Dusty Baker said Kelley will undergo more extensive testing to try to determine the source of the problem but that the initial diagnosis is some kind of nerve trouble, somewhere in the forearm.

“I think there’s still too much uncertainty to really feel anything right now,” said Kelley, who was also vague. “We’ve still got to talk more to the doctors and trainers, do a couple more tests and get a better picture of what’s going on.”

Because he has no firm diagnosis, Kelley would not say definitively that his season is over. The regular season ends a week from Sunday. A return does not seem likely.

Either way, this season will go down as a frustrating one for the veteran right-hander, who signed a three-year deal worth $15 million before the 2016 campaign and entered this year as a candidate to close. Kelley never looked quite right, did not pitch well, and endured two disabled list stints for neck and back trouble before returning earlier this month.

His results revealed a man struggling with something, whether it be injury or mere command; Kelley allowed 12 home runs in 26 innings, meaning his home-runs-per-nine-innings-ratio will be the highest ever for a reliever who completed at least 20 innings in a season. But his velocity — which dropped a full mile per hour from where it was last season — indicated a physical problem might have been to blame. Kelley never said the injury caused his trouble, but he will now have a chance to heal fully. The 33-year-old threw a career-high 58 innings last season, and has not been the same since.

“I feel like here soon in the next couple days, week, we’re going to figure something out, devise a plan and not deal with anything like I’ve had to deal with all year ever again,” Kelley said.

Kelley would not admit frustration, but outfielder Brian Goodwin did. Goodwin has been out since Aug. 16 with a groin injury and participated in both of Bryce Harper’s simulated games this week. Goodwin has also been running sprints at full speed and therefore seems to be nearing a return, though his manager continues to say Goodwin is well behind Harper in his progress.

“If it was up to me, I’d be going right now,” Goodwin said. “It’s not. So I’m going to trust my training staff and my coaches and everybody I’m working with that knows me and has been working with me that has my best interest at hand.”

The Nationals have eight regular season games remaining, and instructional league games begin Monday. If the Nationals deem Goodwin ready to play in instructional league, they seem likely to send him to West Palm Beach to get at-bats. Because Baker suggested he is behind Harper, who is almost ready to play in games, it appears Goodwin would be a long shot for the National League Division Series roster, which might open space for Victor Robles or another young outfielder.

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