Yes, the New York Mets right-hander does belong in that group considering his April numbers: 4-0 with a 0.69 ERA and a 20th-inning save in St. Louis.
In fact, Pelfrey takes a 24-inning scoreless streak into Saturday's start in Philadelphia opposite Halladay -- making that matchup more than an attractive alternative for those who had been craving a Johan Santana-Halladay meeting. Santana instead faces ageless left-hander Jamie Moyer on Sunday night.
"Not a bad substitute at all," said Mets catcher Rod Barajas, who served as Halladay's batterymate in Toronto the past two seasons.
Pelfrey matched the best March/April ERA in franchise history, also produced by Nolan Ryan in 1970. Pelfrey also can set a new franchise record for scoreless innings Saturday, although facing the Phillies' lineup in a hitter-friendly ballpark will be a supreme challenge. The mark currently is held by Jerry Koosman, who tossed 31 2/3 scoreless innings in 1973.
"John Maine might be able to hit it out of there," Pelfrey playfully said so that his locker neighbor could hear. "That park is definitely an airport, or whatever you want to call it. But it'll be the same thing. I'll just go out there and keep the ball down and execute pitches. We'll see what happens."
Pelfrey has made a strong case to emerge as National League Pitcher of the Month for April when the award is announced Monday. Barring another extra-inning save on Friday before the calendar flips to May, Pelfrey's final numbers for the month compare favorably with any other candidate: Lincecum (4-0, 1.27 ERA), Halladay (4-1, 1.80), Jimenez (5-0, 0.79), Brad Penny (3-0, 0.94), Livan Hernandez (3-1, 0.87) or Barry Zito (3-0, 1.32).
"I don't really pay a lot of attention to that," Pelfrey said. "Whatever happens on the side awards, happens. My job is to go out there and put up zeroes and execute pitches and get guys out."
Still, when the San Francisco Giants beat Halladay on Monday, Pelfrey conceded that he may have quietly done a little fist pump.
"Maybe on the side," he said. "But nobody saw it."
The Mets dislodged two-time defending National League pennant winner Philadelphia from first place this week for the first time since last May 29, when the Mets held a half-game lead in the division.
The Mets bus to Philadelphia on Thursday night on a seven-game winning streak, although it's worth noting the Amazins did have an identical surge May 4-10 last season and still finished with 92 losses.
NL ERA LEADERS
Through April 29
Yet after going 9-1 on the homestand, which was capped by sweeps of the Atlanta Braves and Los Angeles Dodgers, manager Jerry Manuel noted: "The way we're going right now, I could probably go in the game and we get a few outs."
Manuel believes the Mets have an edge in the weekend pitching matchups, with Jon Niese opposing Kyle Kendrick in Friday's opener, followed by Pelfrey-Halladay, then Santana-Moyer in the finale. The manager also acknowledged the three teams the Mets faced on their homestand -- the other being the Chicago Cubs -- played poorly during their games at Citi Field. He's curious how the Mets will respond in Philadelphia.
Left fielder Jason Bay went so far as to compare the Mets' start to his experience last year with the Boston Red Sox, who ultimately earned the American League wild card with 95 wins. Like the Mets, the Red Sox opened last season 3-6. Boston then won its next 10 to surge into first place.
"It was almost the exact same storyline, same everything. Eerily similar," Bay said. "It's something like this little run here. Obviously, it's foolish to think you're going to go 9-1 every 10 games. But it's the catalyst to get us above .500. That's not a goal, but it's a stepping stone. You get above that, OK, and then you get a little momentum.
"We're not as bad as we were at 4-8, and I don't think we're going to maintain the 9-1 that we did. But to get us in the spot where we're at now, and to be able to work with that, I think it gets your head above water and lets you play baseball a little easier."
For Pelfrey, being able to exhale has been a key all season. Sure, he added a split-fingered fastball to complement his signature sinker. But arguably as big a key has been his ability to stay composed on the mound. Pelfrey was unfazed Sunday against the Braves while dealing with a slew of runners on base. He battled through five scoreless innings, whereas last year he may have melted down in a similar scenario.
"It's obviously the best month I've ever had in my career," Pelfrey said. "I wanted to get off to a good start, and obviously I've done that. I didn't expect it to be as good as it is. That builds confidence and says, 'Hey, you can be this good. If you do it once, you can do it again.' There's five months left and I'll try to keep it going and repeat it."
So, perhaps Pelfrey-Halladay is a better matchup than Santana-Halladay with first place at stake this weekend.
"It's a long season," Santana said. "I'm pretty sure down the road we'll meet. This is just the beginning, you know? We're going to be here for a while."
Adam Rubin covers the Mets for ESPNNewYork.com. You can follow him on Twitter.