PITTSBURGH — Like many working folks the Mets received a holiday Monday, but this Labor Day break wasn’t planned. 

The tarp remained on the field at PNC Park, and before the Mets and Pirates could get too far into pregame routines, a morning decision was reached for a postponement that left the teams facing a split doubleheader on Wednesday. That it never actually rained Monday afternoon, oh well. 

It was probably a welcomed day off for the Mets, given that Buck Showalter planned to rest Starling Marte and utilize Francisco Lindor as the DH. Now the manager is more likely to keep both players in their normal spots throughout the series, with a Thursday off day scheduled before three games in Miami. 

That scheduled off day looms large, because even if Showalter needs to utilize most of his bullpen in two games Wednesday there is a built in buffer before the Marlins series. It gets messier if Tuesday’s game is also postponed (yes, there is rain in the forecast for much of the day) and the teams have to play Thursday. 

Either way, the Mets know better than to take this series lightly. Losing two of three games at Citi Field against the hapless Nationals over the weekend was one wake-up call, but there are other sobering reminders. 

Start with the fact these last-place Pirates went 5-1 against the Dodgers this season. Yup. That’s baseball, when a team with a payroll ($71.7 million for luxury-tax purposes, according to Spotrac) — lower than what Max Scherzer and Lindor combined ($77.4 million) will earn this season — can handle a colossus. 

But there is also this: the Mets’ demise last season began with two series against the Pirates that wrapped around the All-Star break. The Mets went 3-4 in those games against an awful Pirates team, setting an early tone for their second-half collapse. 

Now the Mets lead the Braves by one game in the NL East with four weeks remaining. Missing the postseason isn’t a realistic possibility, but winning the division and escaping the best-of-three wild-card round would behoove the Mets. Is the glass half empty? Or half full? 

Why the Mets should be worried: Start with the fact the Mets are 50-33 since June 1. That’s a pace to win 98 games, which in most years gives you first place. But over the same stretch, the Braves are 61-24. If the Braves keep that same pace for the rest of the season, they will finish with 103 victories. Just reaching or surpassing 100 wins might not be enough for the Mets. 

Scherzer’s recent side fatigue — he missed nearly seven weeks earlier this season with a strained oblique — is another warning shot. Scherzer is scheduled to take his next turn in the rotation, but to what degree can he push himself during this final stretch? Carlos Carrasco is just returning from an oblique strain and Taijuan Walker’s recent starts haven’t matched his first-half mastery. Plus, the Mets still appear one or two arms short in the bullpen. 

Why the Mets shouldn’t be too worried: Let’s start with the fact the Braves still have seven games remaining against a Phillies team fighting for a wild-card berth. That’s after the Braves finish a West Coast jaunt consisting of stops in Oakland, Seattle and San Francisco. The Mets are finished playing the Phillies and really don’t face anything close to a tough stretch, at least on paper. The Mets still have a trip to Atlanta ahead, but they also own a 9-7 record against the Braves this season. 

Also, Jacob deGrom has passed every test physically to this point and remains an ace that can carry the Mets every fifth game. Edwin Diaz has become the Jacob deGrom of closers. The lineup looked feeble over the weekend, but has mostly answered every challenge this season. Lindor, Marte, Pete Alonso, Jeff McNeil and Brandon Nimmo are too talented to just disappear when they are needed most.