MIAMI -- When the Mets acquired Robinson Canó over the offseason in a blockbuster trade with the Mariners, it signaled New York's determination to return to prominence both in the National League East and postseason landscape.

Five months later, the honeymoon appears to be over as Cano drew heat for his second baserunning gaffe during a disappointing weekend for the Mets. Their 3-0 loss to the rebuilding Marlins on Sunday afternoon at Marlins Park cemented Miami's first sweep since September 2017.

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With a runner at first in a scoreless game in the fourth, Cano chopped the first pitch from Sandy Alcantara behind the plate. Catcher Chad Wallach pounced as the ball spun fair and threw to second base, where shortstop Miguel Rojas took his time going to first because Cano didn't run down the line. Instead, he questioned home-plate umpire Jordan Baker's ruling of the call. Mets manager Mickey Callaway came out to speak to Baker as well.

Cano also grounded into an inning-ending double play in the seventh (but did run it out) as Alcantara continued to face the minimum number of batters en route to his first complete game.

But what made the optics even worse for Cano was that the effort -- or lack thereof -- came two games after Cano confused the number of outs and didn't hustle out of the box during a pivotal sequence in Friday's loss.

"We had an effort level," said Cano, who is batting .245 with three homers and a .667 OPS. "How many balls we hit hard today and it was just right at them? ... It's just a stretch you just go through as a team. There's no reason for us to put our head down, and [we] just got to keep fighting and go out. The best teams in the game, in any sport, they just go through that kind of a stretch."

Added Callaway: "It's just piling up on him and it's tough, man. Stuff happens like that when things are going bad."

New York has dropped five in a row to fall a season-high five games below .500, as rumors concerning Callaway’s future loom over the ballclub.

So who's to blame through the season's first 45 games?

"It's on our whole organization," Callaway said. "We failed so far to this point, and we have to be better."

The starting pitching has been particularly disappointing, although there was a silver lining on Sunday: Syndergaard took a perfect game into the fifth and allowed just two runs over seven strong innings. The flamethrower has a 2.40 ERA and 0.87 WHIP in four May starts.

What about the lineup?

Less than 24 hours after being one-hit, the Mets merely doubled their hit total. Alcantara, who entered Sunday with the fourth-highest walks per nine innings rate in the National League, recorded a Maddux (a shutout in fewer than 100 pitches).

The Mets’ best opportunity came in the eighth, when Pete Alonso opened with a four-pitch walk. After Brandon Nimmo struck out looking, Adeiny Hechavarria bounced a pitch back to Alcantara, whose throwing error to second allowed both runners to reach. Callaway then called on Dominic Smith to pinch-hit for Juan Lagares. Smith got ahead in the count, 3-0, but he grounded into the club's third inning-ending double play of the game on a 3-1 offering.

“Today, you got to give the guy credit,” Cano said. “He went out and pitched. Don’t matter what kind of team they have. We’re at the Major League level. If they’re here, it’s because they can compete, and they can play with anyone. It’s not because we have a better team on paper. That doesn’t mean they can’t go out and play and win a game.”