NEW YORK -- If nothing else, the Mets can be certain that they have not rushed Jason Bay back to active duty.

Though manager Terry Collins quipped that he "wanted him four days ago," Bay will not return to the Mets until Thursday's series finale against the Astros. That will give the outfielder enough time for one last Minor League rehab game Wednesday with Class A St. Lucie, where he homered twice on Tuesday.

"One more day is one more day," Collins shrugged.

The manager has reason to be anxious for the return of Bay, who has missed the first 18 games of the season with a strained left intercostal muscle. Having Bay will allow Collins to slide Angel Pagan back up the lineup to the two hole, where he is most comfortable, while simultaneously providing better protection for middle-of-the-order sluggers Carlos Beltran and Ike Davis.

Though Bay managed only six home runs in 95 games before his season-ending concussion last year, he averaged 31 per year over the previous five seasons.

"I don't want to put it all on Jason Bay," Collins said. "Obviously he's a big piece of the puzzle here -- that's why he's here. He's a very, very good baseball player. He's a fine offensive player. He's a good defender. He runs the bases well. We need him in our lineup. But I don't want to have to think Jason Bay, when he comes back, he's the guy. This is a team of 25."

Finger numbness to land Parnell on DL

NEW YORK -- The numbness in Bobby Parnell's right middle finger will result in a trip to the disabled list. The Mets plan to remove Parnell from their active roster Thursday, after he undergoes an angiogram to determine the exact nature and severity of his injury.

"To have something like this is kind of concerning because I don't know much about it," Parnell said. "But they say that other pitchers have had it and it's not uncommon for them to have it. They've seen it before, which makes me feel better about it."

Because Parnell has not yet undergone his angiogram, the Mets cannot compare his issue to specific case studies across baseball. Angiograms, which use dye to highlight irregularities in the blood stream, can identify anything from mild clots to aneurysms.

"We don't think it's anything serious," Parnell said.

Pitching through discomfort in his right middle finger for more than a week, Parnell reported a worsening of the pain after facing four batters in Tuesday's loss to the Astros. Mets doctors examined him the following day and determined that an angiogram was necessary.

If the issue turns out to be minor, as team doctors believe, Parnell may be placed on an aspirin regimen and avoid missing much time. If it is severe, he could require surgery.

In Parnell's absence, Jason Isringhausen will assume regular eighth-inning setup duties. In 2 2/3 innings since joining the Mets, Isringhausen has struck out four and allowed one run.

The Mets will replace Parnell on the roster with outfielder Jason Bay, who will be ready to come off the DL on Thursday.

Young to pitch in simulated game Thursday

NEW YORK -- Mets right-hander Chris Young plans to pitch in a simulated game Thursday, keeping him on track to return from the disabled list when he is eligible next week.

Young, who has been battling right biceps tendinitis, tested his arm Wednesday with no ill effects. He will start a simulated game Thursday and plans to throw a full bullpen session Saturday. If all goes well, he could return from the DL as soon as Tuesday in Washington.

In Young's absence, Dillon Gee will make his second start of the season Saturday against the D-backs.

Tidbits

Left-hander Pat Misch cleared waivers Wednesday and accepted an assignment to Triple-A Buffalo. ... The Class A Florida State League named Matt Harvey its Pitcher of the Week after Harvey, the seventh overall pick in last June's First-Year Player Draft, struck out 20, walked six and allowed zero earned runs over his first three professional starts, spanning 16 innings.