CHICAGO — Daniel Palencia has been one of the welcome surprises for the Cubs this season.

The 25-year-old fireballer started this year in the minors, returned, and developed into the team’s bona fide closer with a flashy entrance at Wrigley Field.  That’s what made Sunday a bit difficult to watch.

Palencia surrendered five ninth-inning runs in the Cubs’ 6-3 loss to the Washington Nationals, his third blown save of the season, but the most difficult part was seeing the closer crumble to the ground in pain.

He walked off the field with manager Craig Counsell and trainer German Suncin after throwing a 100-mph fastball to Andrés Chaparro. Porter Hodge came in and picked up the final three outs of the frame.

“Danny felt some tightness in the posterior right shoulder,” Counsell said after the game. “Docs have looked at him. That’s all we have right now. Probably let him just calm down a little bit and see how we are in a couple of days, a day or so.”

Counsell said he had a similar pain “maybe a couple months ago,” but that only lasted a day, and Palencia has “been good ever since.”

It’s been a rough month-plus for the Cubs closer. Since Aug. 3, Palencia is sporting an 8.74 ERA and 2.21 WHIP in 11.1 innings across 14 appearances, and Sunday was his second blown save in that time span – he had just one in 16 chances before that.

Sunday’s performance, where he faced five hitters without recording an out, was emblematic of that.

“He left some pitches over the good part of the plate, and they took some good swings,” Counsell said. “Simple as that.”

Palencia was the clear-cut closer for Counsell, who had really settled into a groove with his leverage options late in the game. Sunday was a prime example of that. In a one-run game in the seventh with one out, he turned to left-hander Caleb Thielbar against a pocket of lefties, and he picked up the final two outs.

Brad Keller pitched a perfect eighth inning, picking up two strikeouts and extending his scoreless streak to 20 games (20.1 innings) since July 18, the longest mark among NL relievers. Andrew Kittredge (3.57 ERA) has also been a leverage option for Counsell.

If Palencia is out, Counsell likely turns to Thielbar or Keller to cover the ninth, depending on matchups. Both are fairly inexperienced in that ninth-inning role, though – Thielbar has five career saves, including one this year, and Keller has three — one this year as well. Hodge emerged as the Cubs’ closer last year, picking up nine saves. But he’s dealt with injuries and struggled when healthy, posting a 6.18 ERA this year.

Left-hander Taylor Rogers has the most career saves in the Cubs’ bullpen (83), but he’s struggled since being acquired at the deadline, allowing eight earned runs in 11.2 innings (6.17 ERA) with the Cubs.

The Cubs will hope Palencia is OK and can settle back into the groove he was in earlier this season with the playoffs around the corner.

“He’s done a great job for us all year,” catcher Carson Kelly said. “Especially for a young guy coming in and handling those late innings, it’s really important. He’s been great for us all year.

“I don’t know what it is, but hopefully he’s good to go here in the next day or so.”