SAN FRANCISCO -- Top prospect Zack Wheeler is now a step away from joining Matt Harvey in the big leagues. The Mets on Wednesday promoted Wheeler to Triple-A Buffalo, one day after he struck out a season-high 11 batters in his final start for Double-A Binghamton.

But Wheeler, MLB.com's top-rated Mets prospect, is unlikely to reach the Majors this season. The Mets plan to cap Wheeler at around 150 innings in his third professional season, which should only take him through the end of August.

"I'm anxious to see Zack Wheeler pitch," manager Terry Collins said. "Will it be this year? I would doubt it."

Most scouts believe that Wheeler, 22, possesses a higher ceiling than even Harvey, MLB.com's second-rated Mets prospect entering the year. And Harvey has already electrified the Mets, striking out more batters (18) than anyone in franchise history through the first two starts of a career.

Wheeler, whom the Mets received from the Giants in exchange from Carlos Beltran last July, is certainly enjoying a fine season himself. He completed his tenure at Binghamton with a 10-6 record, a 3.26 ERA and 117 strikeouts in 116 innings, walking 43 batters and allowing 92 hits.

"Everybody's raving about his stuff," Collins said. "It's the same thing with any young pitcher: he's got to learn how to command it."

Mets revive thoughts of extra work for Dickey

SAN FRANCISCO -- At some point this season, the Mets will duck into their laboratory, experimenting to see if R.A. Dickey can successfully pitch every fourth game instead of every fifth.

"It's going to happen," manager Terry Collins said. "I think there's going to be a time when we are going to try it. When that is, I don't know yet."

Collins and pitching coach Dan Warthen have both written out plans to expand Dickey's workload, trying to gauge what effect it might have on their other starting pitchers. There is some disagreement between the two men on how best to proceed, and neither has had a formal discussion about it with general manager Sandy Alderson.

But the Mets are curious to see if Dickey can maintain his success pitching consistently on short rest.

"It's possible the more often we get him out there, the better we're going to do," Alderson said. "But we've got to take into account what effect that would have not just this year on R.A. and on the rest of the pitching staff, but also what effect that would have on R.A. going into next year. So that's very much just in the discussion stage at this point."

The rotation as a whole is currently in flux, with Johan Santana due back from the disabled list next week, Jeremy Hefner pitching well in his absence and Matt Harvey facing a limit of 165-170 innings in his rookie season, threatening his ability to finish out the season. Giving Santana and Chris Young extra rest in their first seasons back from major surgeries certainly would not hurt, and using Dickey more often would allow the Mets to do that.

There is also the matter of personal accomplishments for Dickey, who has an outside shot at becoming the first Mets pitcher to win 20 games since Frank Viola in 1990.

As far back as May, the Mets began considering the idea of using Dickey on short rest, knowing that his knuckleballs place less stress on his arm than traditional pitches. But they nixed the idea at the time, not wanting to disrupt Dickey's routine nor mess with the rest of the rotation.

Now, with nine weeks left in the season, they are reconsidering their stance.

Worth noting

• Closer Frank Francisco pitched a scoreless inning for the second straight day Wednesday at Double-A Binghamton, putting him in line to return from the disabled list Friday. Barring a last-minute setback, Francisco will join the Mets for the start of their series in San Diego.

• Andres Torres felt "much better" Wednesday, according to Collins, but was still suffering the effects of a collision two days earlier with Giants pitcher Madison Bumgarner. Torres, who injured his right thumb on the play, was out of the lineup for a second straight game. He is day to day.

• The Mets recently discussed a trade that would have sent struggling outfielder Jason Bay to Miami for reliever Heath Bell and catcher John Buck, according to FOX Sports. But the discussions never advanced beyond preliminary status.