PITTSBURGH -- No aid was going to come from the outside -- not now, anyway, not in ways that really matter. When the Mets lost Pete Alonso to a left wrist injury that could cost him most of the next month, they knew they would need to turn inward for help.

Largely, that meant asking more of Mark Canha and Mark Vientos, two of the other first basemen on their roster. What those two accomplished -- or didn’t -- over the first portion of the season hardly mattered. What they do now, particularly in Alonso’s absence, could go a long way toward changing the trajectory of this season.

So it was heartening for the Mets to see Canha double home three runs, including the go-ahead run, in a 5-1 win over the Pirates on Saturday to snap a seven-game losing streak -- the team’s longest in almost four years. The victory included strong starting pitching from Kodai Senga, another Francisco Alvarez homer and a standout all-around game by Brandon Nimmo. But it was Canha’s contributions that stood tallest.

Dropped to the nine hole in the lineup in part because of a season-long slump, Canha arrived at the plate in the seventh inning after the Pirates intentionally walked light-hitting left-handed infielder Luis Guillorme. Canha found a Dauri Moreta slider that caught a whisper of the strike zone’s outer edge, then lofted it to right-center field to plate a pair.

The hit, Canha’s first double in nearly a month, gave the Mets the lead for good. He later added another RBI double in the ninth to score Tommy Pham, who contributed a two-hit game of his own.

“Honestly, I haven’t felt like I’ve had a ‘hot streak’ this year yet,” Canha said. “I’m just trying to stay present and have the right attitude toward it all. … Just never say die.”

Things did not begin swimmingly for Canha, who struck out in his first at-bat, grounded into a fielder’s choice in the top of the fifth, and committed a fielding error in the bottom half of the frame. At that point, Canha “just had to shake myself and dig deeper and figure it out,” he said

What’s important is that it doesn’t have to be Canha who lifts the Mets on a daily basis even though he plays the same position as Alonso. It can be anyone, any hitter, any number of names. Nimmo certainly did his part on Saturday, reaching base three times, driving home the team’s first run and making two highlight-reel catches -- including a leaping grab to rob Connor Joe of a potential three-run hit after Senga walked the bases loaded in the third.

But outside of Nimmo and Alvarez, few Mets regulars are hitting with much consistency. So it would certainly be helpful if Canha can at least become one of those somebodies.

“He very quietly has [improved] a little bit,” manager Buck Showalter said. “You see a bunch of the averages creeping up, whether it be [Starling] Marte or Mark or Pham -- guys we know have the track record in the past. Hopefully, little by little, they’re starting to get back there.”

Even after a 2-for-4 afternoon, Canha’s overall numbers -- a .244/.327/.398 slash line with five homers and 21 RBIs -- remain well below his career norms. But he’s been significantly better than that over the past three weeks, with a reduced strikeout rate and an OPS that’s creeping toward .900. It’s not quite a hot streak, as Canha himself noted. But it’s an indication that he may be in the process of shaking away his early-season funk.

The fact that Canha’s improvement is coinciding with Alonso’s absence only underscores the importance of it.

“I always want to fill in and do a good job, wherever that might be,” Canha said. “One of the things I take pride in throughout my career is my versatility and being able to fill in and do a decent job. … Every at-bat, every inning, every situation is an opportunity to redeem yourself.”