Mets closer Edwin Diaz celebrates the final out against the...

Mets closer Edwin Diaz celebrates the final out against the Pirates at Citi Field on Friday, Sept. 16, 2022. Credit: Jim McIsaac

The Mets led by a lot, waiting only for the formality of the final few outs before a happy transcontinental flight home, so Edwin Diaz went to work — not on the mound, but in the bullpen. He didn’t play, again, on Sunday, and he was totally fine with that. He settled for a bunch of practice pitches, a throwaway moment that nonetheless illustrated one form of his professional growth.

Among the keys to Diaz’s superlative season: He has mastered one of his old bugaboos, pitching practically perfectly even when he isn’t pitching often.

The ability to perform well on what Diaz used to consider too much rest — as he will have when he faces Miami or Atlanta this week — and the effort that allows him to do so is, in the eyes of his Mets bosses, a sign of maturity.

“Like any major-league player, you’re going to go through a maturation process,” pitching coach Jeremy Hefner said. “He certainly, just like everyone else, has continued to do his process. He’s trusted it and believed in it, and we’re seeing the results on the field.”

The measures of Diaz’s immense success are aplenty. His 49.6% strikeout rate is tops among all pitchers. His 1.40 ERA is fifth among relievers. He hasn’t blown a save chance in four months.

And here is another: When he pitches on four or more days of rest, he has a 0.00 ERA, 0.47 WHIP and 17-to-1 strikeout-to-walk ratio across 10 2⁄3 innings. He doesn’t get rusty.

As recently as 2021, conversely, Diaz had an 8.18 ERA and 1.55 WHIP (and a still-solid 16 strikeouts and three walks) in 11 innings under such circumstances.

Mets closer Edwin Diaz entered Wednesday night's 2-1 win over the Dodgers in the ninth inning as Timmy Trumpet played 'Narco', Diaz's entrance song, live at Citi Field. Credit: Newsday/Tim Healey

“I don’t mind if they don’t put me in the game for three, four, five, six days,” said Diaz, who most recently appeared last Tuesday in Milwaukee. “I don’t come into the game, but I keep working, I keep working, I keep working. I can make my pitches.”

The problem in the past was that when Diaz did not pitch regularly, he felt he struggled to maintain his mechanics. The frequency with which he got into games became a full-blown thing, cited by him and others as a reason for some of his issues in 2019, his messy first season with the Mets, and 2020, when he again temporarily lost his job as closer.

He told the pitching coaches and managers who cycled through the organization that he didn’t like to go more than a few days without getting on the mound. Even last year, when he blew three consecutive midseason save opportunities, it was because his delivery was out of whack, Mets people said then.

His solution this year: Even when he doesn’t pitch, he keeps pitching — or pretends to, at least.

Diaz does a “dry run,” completing his motion without a ball in his hand, on a bullpen mound before almost every game, Hefner said. And when he goes several days without getting into a game, he has made a habit of completing a full bullpen session at the end of the day, sometimes staying out there after the game’s last pitch to make sure he gets what he needs.

That isn’t all that different from what other relievers do or what he has done previously. But now he is consistent with it.

“His routine is the same every day, where maybe in years past he would fluctuate a little bit,” Hefner said. “The more you can get up there — whether you’re throwing a ball or not throwing a ball — feeling that slope and how you’re moving down the mound is going to help.”

Manager Buck Showalter said: “When he gets a little out of whack, which doesn’t happen very often, he’s able to get right back in sync. It’s the work he does on the side. I don’t think people sometimes realize how much [goes into it]. He’s a pitcher. He locates, he works on his delivery, he wants to be there for everybody. So it’s good.”

Another benefit of Diaz not getting into games for the sake of getting into games: When the Mets do need him, he is available for multiple innings, if necessary. He has pitched only five times this month, but in two of those games (the most recent two), he has gotten more than three outs.

Expect more of that for however long the Mets’ season lasts.

“It’s late in the season, so I just want to get in the game when they need me. If they ask me to pitch, I come pitch any time,” Diaz said. “Early in the season, maybe three or four days off, I want to pitch. Now I don’t mind because I can work in the bullpen, be more rested when they need me for more than three outs.”

Alonso honored. MLB named Albert Pujols and Pete Alonso the NL co-players of the week. Alonso slashed .333/.407/.917 with four homers and 13 RBIs in six games. Pujols’ two-homer game Friday included the 700th of his career. He became the fourth player in major-league history to reach that mark.

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