Phillips said he was made aware of the decision Monday night, and the 25-year-old -- this spring's final roster cut -- was available for Tuesday's game against his former club, the Texas Rangers.
"The one thing I think we know about Zach is that he has good makeup," manager Buck Showalter said of Phillips, who pitched to a 1.35 ERA in 11 spring games. "He [isn't] scared of the competition. He comes in, 'Here it is, let's go'. That's been impressive about him."
Showalter has said multiple times that Philips deserved to make the Opening Day roster, but given the contractual status of most of the Orioles' relievers, the organization decided to exercise Phillips' option instead. Acquired from Texas on July 19 in exchange for infielder Nick Green and cash considerations, Phillips made his Major League debut with a scoreless inning on Aug. 31, and he allowed just one run in eight innings to end the season.
Phillips continued that fine form this spring -- holding left-handed batters to a .095 ERA in the process -- and said he didn't take the decision to send him to Triple-A Norfolk negatively. He continued to go about his business.
"I knew I'd get a chance to come back up here and play again and couldn't do anything about [the roster decision]," said Phillips, who has thrown scoreless outings in three of his last four appearances at Norfolk after a few early struggles. "I feel like my mechanics are in the right place."
Phillips will join Troy Patton and give the Orioles two lefties in the bullpen. Showalter said he wasn't sure if either pitcher would be used in a lefty specialist role just yet.
"I don't think there's enough track record to feel that for sure," he said of the two young lefties. "I think both of these guys, both [Zach] and Troy, have the potential to do both, which is unusual. I hope that they can. I think Troy, with his starting background, and Zach, with his starting background, you can look back at the prospect list two or three years ago and he was right there. He's a guy you like looking at every day. He competes. He's smart."
Berken will head back to Norfolk and start on Sunday after pitching three of the last six days. The right-hander was recalled on Monday and used in the ninth inning, where he surrendered seven runs (two earned).