BALTIMORE—Orioles left-hander Bruce Zimmermann, who’s on the 10-day injured list because of left biceps tendinitis, will remain out beyond that period, according to manager Brandon Hyde.

Zimmermann, who was scratched from last Friday’s start against Toronto, is 4-4 with a 4.83 ERA in 12 games.

“I would expect Zimm to be out two or three more weeks, possibly,” Hyde said.

Hyde said on Saturday that he didn’t expect left-hander John Means, who has a strain in his left shoulder, to pitch until around the All-Star break; the game is on July 13th. Without Means and Zimmermann, the Orioles’ rotation is made up of four right-handers — Jorge López, Thomas Eshelman, Matt Harvey and Dean Kremer — and left-hander Keegan Akin.

Sceroler experiment over: Right-hander Mac Sceroler, who was one of the Orioles’ two selections in the Rule 5 draft in December, was designated for assignment. Tyler Wells was the other Rule 5 selection.

Sceroler, who missed nearly two months because of right shoulder tendinitis, allowed three unearned runs on Monday night and had a 14.09 ERA in five games.

The nephew of Orioles broadcaster Ben McDonald, Sceroler had never pitched above High-A before this season. He was drafted from Cincinnati.

To replace him, the Orioles selected the contract of knuckleballer Mickey Jannis from Triple-A Norfolk.

The 33-year-old right-hander, who began his professional career in 2010, has never pitched in the major leagues. Jannis was 0-1 with a 2.92 ERA in seven games with the Tides.

When Jannis appears in a game, he’ll be the first Orioles knuckleballer since Danny Boone in 1990.

Valdez on the sidelines: César Valdez, who was placed on the 10-day injured list before Monday’s game because of a strained lower back, shouldn’t miss much time, Hyde said.

Valdez pitched in Sunday’s game against the Blue Jays, allowing two run on three hits.

“He went to the training room after the game, and he was getting a little bit of treatment on it,” Hyde said. “His back has been, maybe not 100 percent . He felt good enough to pitch. It ramped up on him after that last outing. I wouldn’t expect it to be too long of an IL stint, maybe 10 days to two weeks, hopefully.”

Santander sits again: Rightfielder Anthony Santander isn’t in the lineup for the second straight game. Santander, who went on the injured list for a month after hurting his left ankle, is still affected by the injury.

“He does feel a little bit better today,” Hyde said. “He should be available off the bench.”

Hyde doesn’t know if Santander will return to the injured list. The Orioles will check on him again on Wednesday.