Britton on exam and expectations for return (O's win 5-4 in 12th)

Orioles closer Zach Britton said he expects to be back on the active roster no later than 45 days following yesterday's examination in Los Angeles.

Britton flew down to Sarasota and will begin his throwing progress in about 10 days, the only timeline that's been presented to him.

"Go from there and feel my way through it," said Brittton, who returned to the disabled list with a strained left forearm and underwent another MRI yesterday during his exam with Dr. Neal ElAttrache.

"He had mentioned the injury was similar to a hamstring strain, whereas you might feel really, really good, but as soon as you go to sprint again, you can reinjure it, so it's very similar to the forearm injury that I have. A lot of it was just about easing back into getting into full intensity back on the mound. He didn't have days in his head when I had asked him specifically if he could just give me days. He just kind of spitballed and told me he would be surprised if I wasn't in a big league game in 45 days, but obviously not to hold him to that because it could be quicker, it could be a little slower. A lot of it is just based on how I feel every day.

I wrote earlier that Britton could miss two months with his latest forearm strain, according to a source, with the Orioles slow-playing him down in Sarasota. He missed 16 days during his first stint on the disabled list and admitted that he rushed back against the advice of the medical staff.

"Sixty days was never something that was ever brought to my attention with ElAttrache," Britton said. "I knew at the same time that a lot of this is going to be based on how I feel every day coming to the field down in Sarasota with (minor league medical coordinator) Dave Walker. We have a good plan in place, kind of went over exactly what we're going to do from a strength training aspect, throwing aspect, so I feel like we're all on the same page on what we need to do. But when it comes from how long I'm going to be out, ElAttrache didn't have a firm number for me. A lot of that was based on how I respond."

Vice president of baseball operations Brady Anderson and a medical representative from Scott Boras' agency also were present during the meeting with ElAttrache.

"Any number that was thrown out was kind of a spitball because when it comes to Tommy John or shoulder surgery, everyone kind of knows this is what it's going to take," Britton said. "But this is a muscle injury, which is good news. There was a hand specialist there with me who told me that muscle gets good blood supply, so it's going to heal. It's just a matter of time and he couldn't even give me a hard timeline, either. He said it could be two weeks, it could be three weeks and you could be ready to go.

"I haven't really thought about days specifically. I'm just looking forward to starting that throwing progression. I already feel pretty good physically, where I am right now. I don't have any symptoms anymore."

The plan calls for Britton to let the forearm calm down before he starts throwing again.

"He asked me how far I throw during the season and I said, 'About 90 to 100 feet,' so obviously there's no reason to go past that distance," Britton said. "It's to get back to what I normally do during the season. That's the whole goal. Do what you normally do. Let's not try to reinvent the wheel. Get me back to form and then the only other positive, I guess, is I'm not a starter, so I don't need the innings built up. The goal is just to be asymptomatic, have no symptoms, be able to recover and not feel anything in the forearm. And then it's going to be easier for me to ramp it up at the back end of my rehab because, as a reliever, I need to be ready for one innings, one inning-plus. Not anything like a starter would need when going through a rehab process."

Brad Brach closed last night's 6-4 win over the Nationals, after Darren O'Day worked the eighth, giving Brach eight saves. However, O'Day has registered two saves and also will be allowed to close.

"A lot depends on health, how we feel they are physically," said manager Buck Showalter. "I'm hoping Mychal (Givens) gets into that mix and Donnie Hart might close a game out for us. I'm hoping another guy steps forward with the potential for that. It's kind of a matchup thing and a health thing. I'm not ever going to broadcast who's not available, but we're going to continue to monitor that real closely.

"Just because it doesn't happen that night doesn't mean they're not capable of doing it, you know? But it's hard to do. We've been spoiled with one of the highest levels of success. Who was better than Zach last year in Orioles history? You'd have to help me. J.J. (Jim Johnson) was really good for us. And Zach will be again. I'm confident of that.

"I think the experience is good for them. But it's almost like, if you anoint one guy ... I think by having that group, everybody feels like, 'OK, this is my inning, my chance to contribute,' whether it's the seventh, eighth or ninth. And we have to have our starting pitchers keep us engaged so those innings matter. But the tough thing is when we're behind in a game or it doesn't look promising and you have to use a guy that's a potential piece for a winning situation and not having him the next day. That's what Zach kept us from having to do, and that's a challenge to managing, especially with six guys down there."

Showalter isn't revealing a timeline for Britton or any specifics with his program.

"Talking to the doctors, it's laid out," he said. "They're all in agreement about the protocol and the way the program is going to work down in Sarasota."

Orioles catcher Welington Castillo threw today for the first time since going on the disabled list with right shoulder tendinitis, and while the session proved encouraging, he isn't expected to be activated before the weekend.

Caleb Joseph continues to start in Castillo's absence. He matched his career high last night with four hits and has raised his average from .111 on April 25 to .240 going into tonight.

Francisco Peña is backing up Joseph and likely will be designated for assignment when Castillo is ready. Peña is out of options and can refuse an outright assignment.

Hyun Soo Kim remains on the bench tonight while Trey Mancini gets the start in left field against Nationals right-hander Max Scherzer. Kim has received only nine at-bats this month, partially because of the abundance of left-handed starters opposing the Orioles and partially because Mancini has been so productive.

"Well, I've got some really good options," Showalter said, adding that the situation has presented one of his most difficult challenges. "I think Kimmy knows that I see him pulling for them. It's hard not to continue to give Trey some looks there. I think he understands that, but it doesn't mean he doesn't want to play.

"The opportunities haven't presented themselves as much as we thought, and Trey has something to do with that. It's not like something (Kim) hasn't done. For Kim, it's kind of what somebody else has done."

Update: The Orioles don't have a hit through three innings and Daniel Murphy homered off Jiménez in the second to give Washington a 1-0 lead. Seth Smith walked to lead off the bottom of the first, and Max Scherzer retired the next nine batters.

Update II: Smith broke up the no-hitter and the shutout with a solo home run to right field with one out in the sixth inning.

Update III: Adam Lind hit a three-run pinch-hit home run to center field in the eighth to give the Nationals a 4-1 lead. Anthony Rendon and Matt Wieters began the inning with singles.

Update IV: Adam Jones homered off Scherzer in the eighth to reduce the lead to 4-2. Enny Romero is pitching the ninth.

Update V: The Orioles scored twice in the ninth on Jonathan Schoop's RBI double and J.J. Hardy's run-scoring single with two outs.

Update VI: Mark Trumbo lined a single into left field off Jacob Turner with the bases loaded and one out in the bottom of the 12th inning to score Jones and give the Orioles a 5-4 victory over the Nationals.

Jones and Manny Machado singled with one out and Chris Davis was walked intentionally.

Trumbo has seven career walk-off hits. The Orioles have won six games in a row and improve to 22-10. They're 5-1 in extras this year.