Latest on Britton, O'Day and more (O's lead 6-4)

BOSTON - Zach Britton threw another batting practice session earlier today at Fenway Park, facing Craig Gentry and Andrew Susac before handling more fielding drills.

Britton increased his pitch count from 15 to 30 by working two "innings."

"It was good," he said. "Threw against Gentry and Susac, so I got a good read. Didn't tell them what was coming this time, so I got a little more realistic look and how the stuff was and it's a little more competitive because they don't know what's coming and they've got a chance to swing, even though they didn't swing a whole lot.

"Just kind of gets that competition going a little bit, so it was good to get that. That's for sure. Probably the best I've felt off the mound in a long time."

Next on the agenda is a one-inning simulated game Tuesday afternoon in Chicago. The same setup could unfold while the club is in St. Petersburg, Fla., to close out its road trip.

"I think it's going to be pretty similar to kind of (today)," he said. "I mean, today you could kind of say was more of a sim game than a BP just because (bullpen catcher) Jett Ruiz called the pitches back there. Roger (McDowell) was calling strikes behind me. Hitters were taking good at bats. If I walked them, they actually walked. They weren't just going in there, watching 10 pitches and getting out. They were working an at-bat. So I'm assuming we'll do a similar next time in Chicago and then go ahead and start a rehab assignment."

Facing two hitters who had instructions to swing increased the energy level for Britton and will make for a smoother transition to his session in Chicago.

"Today, you feel it a lot more than I had before," he said. "Just being competitive, not worrying about delivery as much. All the other things that flood your mind when you're coming back from an injury. When the guys can actually swing you get a little more competitive and you focus more on making better pitches than you would if the other guy is just standing up there and that's nice.

"Craig and Susac, they're going to give me a nice look. They're not just going to swing at everything. And that's why I wanted them to do it, because I know these guys have 100-200 at-bats under their belt and they're seeing the ball. So they're not going to just chase stuff that guys up here wouldn't chase. They're going to give me a good look, so I think it's going to be good for me going forward."

A sim game should closely replicate everything Britton did today.

"It's more about me simulating an inning, so today if I throw four balls and walk a guy, act like there's a guy on first," he said. "That's actually what you're doing. The BP, you have the screen up there and it's more about just getting your pitch count up, where, especially the last 15, we were like, 'Hey, let's work it like an inning.' If you walk Craig or Susac, act like there's a guy on first. You give up a hit. Things like that. And I think that's going forward, maintaining that focus the next two times before I get in a rehab game."

Darren O'Day threw in the bullpen today, but he's not expected to come off the disabled list Saturday.

"That was better than the last time, so that was encouraging," said Orioles manager Buck Showalter. "Still not imminent today or tomorrow, but that was encouraging. Still not quite there. Got to get what's still lingering out of there before we activate him.

"If he comes in tomorrow and he doesn't feel anything, we'll move pretty quickly, but until he comes in the next day and doesn't have any residual discomfort, then we're not going to go there. Obviously, he's worth waiting on and we want to get it right the first time."

O'Day is on the disabled list with a hyperextended right elbow. He was eligible to return on Wednesday.

"There's just one discomfort we need to get out of there," Showalter said. "The good news is that it's structurally fine."

Colby Rasmus received more at-bats today at extended spring training while recovering from a hip injury. Rasmus should bve ready for a rehab assignment around May 24.

"He's doing well down there," Showalter said. "He seems to be responding good to that injection."

Miguel Castro remains a possibility to start on Sunday despite working 1 1/3 innings last night, but David Hess appears to be the frontrunner.

"I think we've got an idea what we're going to do, but kind of waiting on how the weather might affect it," Showalter said. "Doesn't look good for tomorrow, huh? Sunday doesn't look as good as what they're telling me."

Showalter spoke again today with Kevin Gausman, who allowed his first five stolen bases of the season last night. Gausman twice threw over to first base after the runner already broke for second and was halfway to the bag.

"Kevin's usually pretty good at putting it behind him, a good start and a bad start, but that one kind of stuck in his craw," Showalter said. "We had like four walks, three 90-feet we gave up, a play we didn't (make). That's eight baserunners and he gets frustrated with that because he takes a lot of pride in it.

"Sometimes, when you're that quick to the plate, people know you don't necessarily throw over there a lot because people aren't running, so if you can figure out when he's not coming over completely ... But we've just got to get a step-off there. It's a pretty easy thing to defend. Kevin's good at that too. It's something he'll correct.

"You go through a lot of different things. Are they seeing the throw-over sign or has the first base coach or runner picked up something on his delivery that tells you he's going to the plate? There's about eight check lists and we're looking at all of them, but I've got a pretty good idea what was going on."

Showalter said he reviewed tape of the game and plate umpire Tony Randazzo actually did well calling balls and strikes.

"I was wrong, he was good," Showalter said. "That was one of the better games we've had this year."

Update: The Orioles took a 1-0 lead in the first inning after loading the bases with one out. Trey Mancini scored on Mark Trumbo's grounder to third base after a leadoff walk and Manny Machado's double.

Update II: Mookie Betts homered off Alex Cobb with two outs in the third inning to tie the game 1-1.

Update III: The Orioles scored four runs in the fourth inning after loading the bases with two outs and lead 5-1. Adam Jones produced a two-run, tiebreaking single and Machado followed with a two-run single off the Green Monster, making him 3-for-3 tonight.

Update IV: Cobb gave up two runs in the fifth to reduce the lead to 5-3. Betts had an RBI double and Andrew Benintendi followed with an RBI single.

Update V: Jonathan Schoop homered off knuckleballer Steven Wright in the seventh to give the Orioles a 6-3 lead.

Update VI: The Red Sox scored an unearned run in the eighth, charged to Mychal Givens, after Mancini dropped Xander Bogaerts' fly ball for an error. Brad Brach replaced Givens and Eduardo Núñez doubled to score Bogaerts and reduce the lead to 6-4. Betts popped up with the bases loaded to end the inning.