The Cubs pitching staff has been hit hard by forearm injuries this season.

Michael Fulmer is the latest Cubs pitcher to land on the IL due to a forearm strain — the second time in the last month Fulmer has dealt with the issue.

The Cubs placed the veteran right-hander on the 15-day IL Saturday and recalled Daniel Palencia (who was just optioned Friday to make room for Marcus Stroman to come off the IL).

Fulmer was on the IL from Aug. 26-Sept. 11 with the same forearm issue and only made 1 appearance this week, picking up a save with 0.2 innings of work Monday in Colorado.

“The Fulmer thing is rough,” manager David Ross told reporters Saturday in Arizona. “He was working his way back. He didn’t recover well from the Colorado outing. Just hoping we can calm that thing down and get him rested.”

Fulmer has been a key figure in the Cubs bullpen this season after signing a 1-year, $4 million deal in the offseason as a free agent. He began the year as the team’s closer but went 1-for-3 in save situations in the first couple weeks and ultimately was moved to a lower-leverage role.

The 30-year-old got back on track in late May and over his last 35 outings, he sported a 2.48 ERA with 8 holds and 41 strikeouts in 36.1 innings.

“It’s a tough loss,” Ross said. “He’s somebody that’s been really important to our success down there. He closed out that game in Colorado for us but wasn’t able to recover as well as he should. Just getting to the back end of the season is tough when guys are banged up.”

The Cubs are already down Adbert Alzolay — who is also on the IL with a forearm injury — and just got veteran Brad Boxberger back last week after he missed 3 months with a forearm injury of his own.

With only 16 days left on the schedule, it’s doubtful Fulmer returns in the regular season.