BALTIMORE -- Richard Bleier, one of the few bright spots in the Orioles' 2018 campaign, told reporters prior to Saturday's 5-4 loss to the Marlins at Oriole Park at Camden Yards that he will undergo surgery to repair a Grade 3 tear in his left lat. Bleier will be out for the remainder of the season, with the goal of rehabbing to be ready in time for next Spring Training.

After undergoing surgery on Tuesday in New Jersey, Bleier will head down to the Orioles' facility in Sarasota, Fla., to begin rehab. Bleier said he has not yet received a firm timetable, but it should come after the operation.

Bleier sustained the tear in eighth inning of the 5-1 loss to the Red Sox Wednesday, wincing in pain the moment he let go of the fifth pitch of his relief outing.

"It felt like I got shot in the back. It was pretty unpleasant," Bleier said. "I followed through and made the pitch I was trying to make. And then kind of after the pitch, I felt it, and it was definitely uncomfortable to the point where I didn't even know if the guy got out, or if it was a hit, until I was in the training room and I asked finally. They said he got out, so that's good."

In his 31 appearances in 2018, Bleier amassed a 3-0 record and 1.93 ERA in 32 2/3 innings pitched. Only Donnie Hart, who has appeared in six games for the Orioles, and Zach Britton, who has appeared in two, have a lower ERA than Bleier.

"It's tough because I would love to pitch every single day the rest of the year still. It's frustrating for myself, and I feel like I let the team down, honestly, by getting hurt," Bleier said. "When we start playing well, I won't be there for that. That's going to be a good time, when things turn around here and not being here for that is definitely going to be frustrating. That aspect is pretty upsetting."

Bleier is under team control for four more seasons, with the latter three being arbitration eligible.

"I'll take the exact same to be honest with you," Bleier said of his hopes for an eventual return. "I feel like I was pitching pretty well lately, and I would love to just pick up where I left off. And I'm sure it'll all work out like it [had been]."

Cashner could return Wednesday or Thursday

The Orioles were confident that as soon as starting pitcher Andrew Cashner landed on the disabled list with a lower back strain, he would only miss one start. It seems like that will hold true.

Manager Buck Showalter said Cashner will have a work day Sunday, and barring any setbacks, he should return during the three-game series at the Nationals in the upcoming week.

Beckham, Rasmus should be back next week

The Orioles' struggling bats could receive reinforcements in the coming week, with outfielder Colby Rasmus and third baseman Timothy Beckham expected to come off the DL after their current rehab stints.

Rasmus went 2-for-4 with a double, homer, two runs scored and three RBIs for Class A Advanced Fredrick Friday night.

With Double-A Bowie, Beckham went 0-for-2 with a walk and a run scored in his first rehab game Friday night. He will DH when Bowie plays Portland tonight, and will get back in the field by Sunday.

Father's Day details

Major League Baseball teams will do their part to help the fight against prostate cancer, raising funds and awareness for the disease -- and other important initiatives -- leading up to Father's Day.

The O's, amid the popular "Have A Catch" campaign, will again host Father's Day Catch on the Field, presented by Pennington Grass Seed. The sold-out charitable event offers fans an opportunity to enjoy a Father's Day catch in the Oriole Park outfield prior to Sunday's series finale against the Miami Marlins at 1:05 p.m. ET. Last year, the program raised more than $20,000 for the Orioles Charitable Foundation.

MLB's effort also includes the annual Prostate Cancer Foundation "Home Run Challenge," which has given fans the chance to make a one-time monetary donation or pledge for every home run hit by their favorite team from June 1 through Father's Day, all the while tracking where their team stacks up in a "Team vs. Team" competition. Every dollar donated through the Home Run Challenge goes to PCF to fund critical research to defeat prostate cancer.

As of Friday, more than $1.85 million has been pledged via the Home Run Challenge this year. Since its inception, the Home Run Challenge has raised nearly $50 million for PCF, the world's leading philanthropic organization funding and accelerating prostate cancer research.