PORT ST. LUCIE, Fla. -- In Edwin Díaz’s eyes, he is the Mets’ closer.

Díaz understands there are people who believe his strong performance in 2020 was the product of a small sample size in a short season, or of no fans in the stands, or of anything else that might explain away his success. He understands that manager Luis Rojas won’t publicly commit to him as the Mets’ sole closer. He also knows he’s been a dominant reliever for most of his Major League career, with the exception of his first season in New York.

Given all that, Díaz reported to camp intending to pitch the ninth.

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“Every offseason, I prepare myself to be the closer of the team,” Díaz said through an interpreter. “I think last season was really important for me. I had a tremendous season last year. I’m not the one who makes the decisions, but I know my mindset and my preparation is to be the closer of this team.”

The differences between Díaz’s performances in 2019 and ’20 are stark. In his first season as a Met, Díaz blew seven saves, took seven losses and posted a 5.59 ERA. A year later he recovered from a rocky start to become a dominant reliever over the final five weeks of the season, producing a 1.75 ERA overall. He allowed one run over his final 12 appearances and, most notably, cut his home run rate by two-thirds.

A quick look at his metrics shows the difference.

2019

K rate: 15.4 per nine innings
HR rate: 2.3 per nine innings
Hard-hit rate: 45.7 percent

2020

K rate: 17.5 per nine innings
HR rate: 0.7 per nine innings
Hard-hit rate: 38.6 percent

Díaz said that his adjustments were subtle, mostly revolving around a return to the mechanics that helped him put late movement on his pitches and become a dominant closer in Seattle from 2016-18. Without realizing it, he drifted away from those mechanics in his first year with New York. By the time he realized the issue, it was too late.

Following that season, he sought help from Hall of Famer Pedro Martínez, whom he continued talking to this winter. In that and other ways, Díaz tried to perfectly mimic his 2019-20 offseason as he prepared for 2021.

“Considering that I had such a good season, it’s really about staying in the same routine, the same rhythm,” Díaz said. “Obviously, it was only 60 games, but those 60 games were competitive. It was a competitive season. And those games are competitive every single day. So I think it’s about staying in the same rhythm and the same consistency to be able to have the same type of year 2021.”

The question is whether it will be enough for a pitcher who lost the closer’s job in each of the past two seasons. One of the Mets’ primary ninth-inning alternatives, Seth Lugo, is rehabbing from elbow surgery and won’t be ready for Opening Day. But the Mets brought in Trevor May, who has experience as a fill-in closer, and they still employ former standout closers Dellin Betances and Jeurys Familia. In addition, Rojas has discussed being more proactive about seeking strong matchups -- for example, using a lefty in the ninth if the situation calls for it.

“There are just so many scenarios in a game,” Rojas said, noting that he prefers having the flexibility to use Díaz in earlier innings if the situation is higher leverage.

“Diaz had a tremendous year -- one of the best years for a reliever in the season, I thought,” Rojas continued. “There’s a lot of guys here that can pitch at the end of games. For me, Sugar … may be the guy that gets the most chances. We have high trust in him. The stuff is tremendous, electric. You see his numbers.”

In other words, Díaz is the Mets' closer, even if he doesn’t carry the official title. He probably won’t have the longest rope of any closer in the game, and there may well be times when somebody else pitches the ninth. But for the Mets to be at their best, they know, they’ll need Díaz to be the Díaz of old.