TAMPA, Fla. -- By the time their regular season begins Monday against the Boston Red Sox, there may be a better squad of New York Yankees on the disabled list than on the field at Yankee Stadium.

The Yankees will add starter Phil Hughes to an already star-studded group that will open the season on the DL, including Derek Jeter, Alex Rodriguez, Mark Teixeira and Curtis Granderson.

Although the move was expected -- Hughes lost two weeks of spring training back in February with pain in his upper back from a bulging disk -- manager Joe Girardi made it official after the right-hander threw a minor-league game at the team's developmental complex Wednesday.

Girardi said Hughes will not accompany the team to New York but will be left behind for extended spring training, which begins here Monday. Although his DL stint will be backdated to March 22, allowing the Yankees to activate him as early as April 6, the target date for Hughes' first major league start is April 11.

"I think the plan is to give him two more starts," Girardi said. "But that doesn't mean it necessarily has to happen. We might feel that he's ready after the next one. We've just gotta be prepared for it more than anything."

Hughes worked five scoreless innings against the Lansing Lugnuts, a Toronto Blue Jays Class A affiliate. He allowed five hits, struck out four and walked none, getting his pitch count up to 81. The Yankees would like to see Hughes throw 95-100 pitches in a minor league game before activating him.

"I feel like I threw the ball OK, probably better than last time," said Hughes, who said his velocity has been between 90-91 mph. "I feel pretty good. It's just a matter of them feeling like I'm ready to go."

Without Hughes, the Yankees' rotation will be CC Sabathia, Hiroki Kuroda, Andy Pettitte, Ivan Nova and David Phelps, who will make the April 6 start in Hughes' place.

Girardi and Yankees pitching coach Larry Rothschild refused to commit to a Hughes start on April 11, when the Yankees are scheduled to play the last of a four-game series against the Indians in Cleveland, although Hughes thinks he'll be ready by then.

"That's hard to say, because he still needs to be stretched out, and you have to see if the stuff stays the same," Girardi said. "I don't know how hard he's throwing now, but the first four innings he was pretty consistent."

Hughes went 16-13 with a 4.23 ERA last season, tying for the team high in wins with Kuroda. He also allowed 35 home runs, second-most in baseball behind then-Angels starter Ervin Santana.

"I think stamina-wise he's still got a little ways to go," Rothschild said. "He took a good step today, but it's still not easy to catch up that much ground. So we'll see where it goes."