Of late, it's been as a starter.
Phelps will make his fourth consecutive start on Saturday, taking Freddy Garcia's previously scheduled spot. Of his six career starts, none have come against Baltimore, but he has five scoreless innings of relief against the O's.
But of all of his appearances this season, Saturday's might be the most important. Baltimore's 6-1 win on Friday pulled the Orioles to within two games of the Yankees for first place in the American League East.
But Girardi has insisted that the O's haven't put any added pressure on his team.
"I think you can walk in the clubhouse and realize there's no sense of panic," Girardi said prior to Friday night's series opener. "Everyone has a smile on their face and everyone came to work today ready to go. Guys are taking their early BP. It's business as usual. The thing about a season is you're going to go through ups and downs, and it's how you manage it."
Standing in New York's way on Saturday is Wei-Yin Chen, who took a hard-luck no-decision against the White Sox his last time out after allowing just two runs -- one earned -- in what would ultimately be a 4-3 Orioles win.
Chen has fallen into a pattern in August of following his good starts with bad ones. After tossing seven innings of shutout ball against the Rays on Aug. 4, Chen gave up seven earned runs over just 4 2/3 innings on Aug. 9 against the Royals. He rebounded by allowing just one run against the Red Sox his next time out, but allowed five over as many innings against Detroit in his next start.
"Every game is challenging for me, and every game is challenging for this team," Chen said after his start against the Tigers on Aug. 19. "Right now, my only hope is to help the team get to the playoffs. That's my only dream right now, my only goal."
Yankees: Pettitte takes step forward in recovery
Andy Pettitte's recovery from a fractured left ankle moved to a new level on Friday.
Pettitte threw 20 pitches in a bullpen session, though admitted that he didn't fully exert himself in the process. Still, the session gives a much-needed confidence boost for Pettitte, who hasn't pitched in a game since June 27.
"It was huge," said Pettitte. "I'm sure that you guys talking to me could tell that I was getting a little paranoid about how this thing's going to feel. Today was good. I didn't get out there and push off as hard as I could and let it fly, but I was just introducing myself back to the mound. I felt really comfortable, so that was a good thing. And my arm felt just free and easy. That was another good thing."
Pettitte went 3-3 with a 3.22 ERA in his first nine starts before he took a batted ball off his ankle in a June 27 start, an impact that broke his ankle and mandated a six-week recovery.
Orioles: Wolf welcomes new role in Baltimore
Buck Showalter now has another left-hander to use out of the bullpen.
The Orioles officially added veteran free-agent pitcher Randy Wolf to their 25-man roster on Friday after he was released last week in the final year of a three-year, $29.75 million contract with the Brewers.
Wolf was 3-10 with a 5.69 ERA in 25 games -- 24 starts.
"This has been the most frustrating year of my career, because I'm probably throwing a slight bit harder than I was last year, I feel better physically than I did last year," Wolf said. "And I know my stuff isn't that much different. I think my location hasn't been as good.
"It's been a nightmare year, no doubt. To me, I look at going to Baltimore and going to a new team as maybe a silver lining in a nightmarish year. It's exciting to go to a new team and kind of have a rebirth and try to help out in a new role."
Wolf has just five career relief appearances in 371 Major League games, but he said Friday he was aware of the role change and welcomed the idea of signing with Baltimore.