Back in Summer Camp, the most significant Mets lineup question was whether the team would bat Robinson Canó third. For most of his life, Canó had been a three-hole hitter. The Mets stuck with him in that spot for dozens of games last year regardless of how deeply he slumped, but public pressure was mounting to drop Canó in the lineup.

Knowing the future of the Mets’ offense surely revolved around Pete Alonso, Jeff McNeil and others, manager Luis Rojas acquiesced, regularly slotting Cano sixth or seventh early this season.

So it was telling to see Canó batting above Alonso on Monday. The former, just back from the injured list, came into the night flirting with a .400 batting average. The latter, fresh off a mental and physical health day off, was flirting with the Mendoza Line. But for at least one night, their trend lines ran parallel as Canó and Alonso each hit two homers in the Mets’ 11-4 thumping of Miami at Marlins Park.

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“No matter who we face,” Canó said, “we can compete with anyone.”

Returning to his usual position of second base after spending the weekend as New York’s designated hitter, Canó hit a two-run homer in the third inning, then crushed a 441-foot homer to right-center field in the sixth -- his longest in three years. In accomplishing that feat, Canó tied Ryne Sandberg for the most multihomer games by a second baseman in Major League history.

Not to be outdone, Alonso hammered a solo homer down the left-field line in the fifth inning, then went back-to-back with Canó in the sixth. The Mets hope the effort will help the reigning National League Rookie of the Year Award winner become a more consistent power threat in the middle of their order.

“We did not talk about the position where he was hitting in the lineup pregame or even now postgame,” Rojas said. “There’s a lot of things that can happen just from having the order itself, and Pete ended up being sixth tonight.”

Monday’s win went to reliever Chasen Shreve, who followed Robert Gsellman and struck out five of the seven batters he faced. But it may as well have gone to Canó, who batted fifth in the lineup, or Alonso, who hit lower than fifth for the first time in his career. Since spring, Rojas has stressed the fungibility not only of his starting nine, but of various bench players -- Luis Guillorme, anyone? -- who can be part of that mix as well. Within the walls of the clubhouse, dropping Alonso behind Canó was not a big deal.

In New York tabloid and talk-radio culture, it was more significant not so much because of what it meant for Canó, but because of what it portended for Alonso. Coming off a 53-homer season, Alonso had spoken often about avoiding a sophomore slump. But he struggled in Spring Training, scuffled in Summer Camp and labored again once the season began.

For every big game on Alonso’s ledger, there were multiple forgettable ones. Concerned, the Mets tinkered with his swing, tried him at DH and rested him more often than usual, all in an effort to induce a performance like the one Alonso provided against the Marlins. To Rojas, as encouraging as Alonso’s two home runs were the nastier pitches he did not chase, breaking some bad habits from earlier in the season.

“If he can be consistent doing that and bring it back tomorrow, we’re going to see some really good at-bats and some really good results moving forward,” the manager said.

Future lineup assignments will depend upon how Canó and Alonso fare. The Mets are cautiously optimistic that Canó, now batting .412 at age 37, can continue to produce as a middle-of-the-order hitter. And they’re entirely dependent on Alonso, whose ceiling is one of the best power hitters in baseball -- no matter when and where he hits.

“It was great to see him come out tonight in that way, in a big way, and hit two homers,” Canó said. “I’m so happy for him. And I can’t wait to see him be the same guy that he was last year.”