"If it feels good on Sunday," Warthen said of Maine's right shoulder, "I think we'll be talking with [general manager] Omar [Minaya] and [manager] Jerry [Manuel] about activation on Monday."
Yet only minutes later, Warthen's mood had changed.
"If I was to be a prognosticator," he said, "I would say the chances of him pitching are pretty slim."
So it goes for Maine, a starter who could help the Mets in relief, but likely won't; one who continues to work toward a return, even if the Mets consider it improbable. Maine will pitch a simulated inning against hitters on Saturday afternoon, and if he feels no pain in his arm -- and, more importantly, if Warthen and the Mets deem him fit for big league action -- then he could join the team in a relief role before Monday's game at Shea.
But if he does feel pain, or if the Mets remain unconfident in his velocity or his mechanics, then Maine's season will likely end.
"At this point in time, it's make or break," Warthen said. "We have 10 games left to go. Hopefully, we're going to the postseason. We want to find out if this guy is going to be available to us in the postseason. We don't have time to play three games and say, 'Oh well, we'll take a chance.'"
Maine, for his part, didn't share his pitching coach's pessimism, pointing to Saturday's schedule of events as evidence that he can -- and perhaps will -- still return. He will throw 15 to 20 pitches, and will attempt to use as much velocity as he can muster.
And even more important than Saturday's performance will be how he feels Sunday -- the dreaded day after.
"If it doesn't hurt, the decision's in their hands," Maine said. "And if they come back and say no, they say no. If they want me to pitch, I'll be ready."
Maine has been on the disabled list since Aug. 25 with a bone spur in his right shoulder, which he says is grating against his right rotator cuff when he pitches. Yet doctors have confirmed that pitching won't exacerbate the injury, and so Maine began throwing on Monday for the first time in three weeks.
Saturday's simulated game will mark his first time pitching to hitters since landing on the disabled list.
"I'm going to tell them exactly what I feel," Maine said. "Now, it's the time to be 100 percent honest. If I'm hurt out there pitching, I'm not doing anybody any good."
Anthony DiComo is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.