Thirteen games remain. It’s not much. The Mets’ playoff hopes took another significant hit on Sunday, when a middle-innings bullpen implosion sent them to a 7-3 loss to the Blue Jays in Buffalo, N.Y. The Mets (21-26) are now five games under .500 and will, in all probability, need to win at least nine of their remaining games to make the postseason.

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Even that might not be enough after relievers Brad Brach and Jared Hughes walked the first four batters in the sixth at Sahlen Field en route to a five-run Blue Jays rally. Brach walked all three batters he faced before Hughes issued another free pass to force in a run. Hughes then gave up a bases-clearing double to Santiago Espinal and an RBI single to Danny Jansen, turning a one-run game into a breezy Jays victory.

“We’re still right there,” third baseman Todd Frazier said. “But we’ve got to win more games.”

Frazier added that “crazier things can happen,” which is certainly true. While the Mets’ path to the postseason may be difficult, it’s not impassable. It looks a little something like this:

1. deGrom must win the NL Cy Young (or at least come close)
It’s probably unfair for the Mets to ask Jacob deGrom for something approaching perfection every time out, but deGrom requires it from himself, anyway. He’s scheduled to pitch three more times over the remainder of the season, and if those starts look anything like his first nine, he’ll probably win his third straight Cy Young Award.

Essentially, the Mets can’t afford to lose any of deGrom’s starts the rest of the way. From 2018-19, they were 28-36 in deGrom’s starts despite his excellence in nearly all of them. This year, they’ve won seven of deGrom’s nine outings. The way he’s pitching, another three seem manageable.

2. Somebody besides deGrom and Lugo must step up
Even assuming deGrom stays near-perfect and Seth Lugo gives the Mets five-plus solid innings each time out, the Mets must play seven of their final 13 games with other pitchers on the mound. David Peterson offered an encouraging start on Sunday, allowing a two-run homer in five innings, but manager Luis Rojas cut the rookie short after 81 pitches, not wanting him to face the heart of Toronto’s order a third time.

“I don’t ever want to have the ball taken from me, but that was the decision, and my work was done at that point,” Peterson said. “The rest I could do was cheer on my teammates and try to back them.”

Perhaps given a longer leash, Peterson will change the rotation equation for the Mets down the stretch. Perhaps Rick Porcello will, or even Michael Wacha or Steven Matz -- two pitchers recently bounced from the rotation. The Mets don’t particularly care who, they just know it has to be someone.

3. Alonso must get hot and stay hot
It has been a season of fits and starts for Pete Alonso, who has picked up his power production -- but not his overall hitting production -- in recent weeks. Over his last 13 games, Alonso is 11-for-52 (.212). Five of those hits were home runs.

That’s not to say Alonso needs to become a singles hitter for the sake of lifting his batting average. He simply needs to be more consistent overall, drawing walks and reaching base more often when he isn’t hitting the ball over the fence. In three games this weekend, Alonso finished 1-for-13 with a single and six strikeouts. That can’t happen in future series if the Mets want their offense to click.

“They’re still pounding him in a lot,” Rojas said, noting that the inside fastballs are leading Alonso to chase outside breaking balls off the plate. “He needs to make the adjustment. We’ve seen him good, and then all of the sudden he has two games or three where he doesn’t have the same approach. He just needs to stick to his pitches, to his strike zone, to what makes him be successful.”

4. Díaz must not blow another save
Edwin Díaz has quietly been better for the Mets in recent weeks, striking out 11 over five straight scoreless appearances. Since the start of August, Díaz owns a 1.08 ERA with 34 strikeouts in 16 2/3 innings. He has also reestablished himself as the Mets’ primary closer now that Lugo is in the rotation, Dellin Betances is on the injured list and Jeurys Familia has proven inconsistent.

But Díaz has only had one save chance in the last two weeks, and his history -- 11 blown saves and eight losses the past two seasons -- is not one that breeds implicit trust. The Mets simply cannot afford a single Díaz slip-up over the next two weeks.

5. The Mets must win every remaining series
And even that might not be enough. The Mets would do well to begin with a sweep of the Phillies in a three-game set that begins Tuesday. The Phillies lost both halves of a doubleheader with the Marlins on Sunday, and they would fall into a virtual tie with the Mets in the National League standings if they lose all three upcoming games.

Short of that, the Mets must win at least two of three in Philadelphia, then win every other series the rest of the way. That would allow them to finish with a .500 record, at least giving the Mets an outside chance of making the postseason.

“You can’t really look at it like we need to go out there and win every game from here on out,” Brach said. “But I think we all know that we’ve got to go to the field and just try to do the best we can every single day.”