NEW YORK -- The Mets' rotation has produced only one performance of more than six innings this year. New York's bullpen is averaging almost four innings per game. That might sound like a recipe for a losing record, but the Mets have the best one in the National League.
There is one clear and obvious factor behind it: The relievers have performed brilliantly in assembling the second-best bullpen ERA in baseball (1.67). However, there are a few other factors that are contributing and worth noting.
The team has already had four days off because of the schedule and a snow postponement in Philadelphia. The Mets' most reliable relievers -- used often so far because of all the leads to protect -- have been able to get days off because of that. As manager Mickey Callaway said, the club has not paid "a price yet because we've had a lot of off-days. We would have had to go a little bit different route" without them.
Robert Gsellman and Seth Lugo -- both originially starters who pitched in the rotation last season -- have been converted into relief pitchers. Both righties are capable of coming into a game and throwing multiple innings, which both have several times and with great effect. Callaway said the key to a high-performing bullpen is that "guys are rested the right way and we're not overtaxing them on a weekly basis -- now there's going to be times when they throw three out of four and they'll have to, so as long as we don't just continue to do that over and over and over again I'm going to be happy with no matter how many bullpen innings we throw."
If the relief corps needs to pitch three or four innings in a game and Gsellman or Lugo is pitching two or three of them, it lightens the load across the board.

And Callaway has a long enough view to think of his bullpen as more than just the seven pitchers on a given night. He knows that there are pitchers at Triple-A Las Vegas who can perform and so he sees a well of nine to 10 whom he can use over several days.
"It does allow you to know that you're not going to use up all your bullpen and not have everybody the next day," Callaway said. "Two optional relievers, 2-3 optional relievers, you could get 2-3 guys if you want to."
Still the members of the current starting rotation -- Noah Syndergaard, Jacob deGrom, Matt Harvey, Steven Matz and Zack Wheeler -- probably can't continue to pitch just five or six innings in a start before it could start to cause fatigue among relief pitchers. Wheeler was the only one to have thrown a pitch in the seventh inning entering play Saturday.
"It'd always be nice to have them go seven or eight," Callaway said. "If they deserve to go back out and makes sense for our team to win then we'll send them out there. ... There's no reason to push anybody."
Catching update
Tomas Nido will team with starter Syndergaard to form the Mets' batter on Sunday, according to Callaway. After a brutal two days during which starter Travis d'Arnaud was diagnosed with a torn elbow ligament that requires season-ending surgery and backup Kevin Plawecki suffered a broken hand on a hit-by-pitch, Jose Lobaton was called up and started Friday and Saturday.