PHILADELPHIA — Whenever the Mets dry off from the champagne showers, they will need to sober up in the face of the class of the NL East.
The Phillies await in an NLDS matchup that begins Saturday at Citizens Bank Park, the next step for a Mets club that has slayed some demons in Atlanta and Milwaukee.
Rob Thomson’s crew has its starting pitching lined up and its bullpen fully loaded.
The Mets, who did not have a top-tier starting option for Game 1 and are stunningly turning to Kodai Senga, will begin in a hole — which is nothing new for this group.
They lost their first five games, were 11 games under .500 on June 2 and appeared to be on the verge of elimination twice in the past week.
Instead, they jolted the Braves in the ninth on Monday and astonished the Brewers in the ninth on Thursday.
The Phillies, who moved into first in the division on May 3 and never relented, winning the NL East by six games, were far less dramatic.
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The Post’s Mark W. Sanchez takes a look at how the Mets and Phillies match up for the playoff showdown:
At the plate
Getting on base
Both are among the stronger teams in baseball at working their way on base, but the Phillies are among the strongest.
Bryce Harper (.373 OBP) lives on base, and Philadelphia boasts three other qualifiers (Kyle Schwarber, Trea Turner and Alec Bohm) who finished the season above a .330 OBP. The only Met to do so was Francisco Lindor (.344 OBP).
Edge: Phillies
Power
Both can slug, the Mets finishing with the sixth-most home runs and the Phillies seventh.
Especially at Citizens Bank Park, there is potential for plenty of game-changing moon shots. Has Pete Alonso, Thursday’s hero, awoken?
Can Mark Vientos establish himself as an October performer?
Will Harper and Schwarber’s playoff legends grow?
Edge: Even
On the basepaths
The Mets are quite proud of their baserunning, successful on 82.8 percent of their steal attempts for the second-best efficiency in franchise history.
The Phillies, though, are better.
They have stolen at about the same percentage while thieving 42 more bases than the Mets.
Only Lindor (29) stole more than 17 bases this season for the Mets while Bryson Stott (32), Johan Rojas (25), Turner (19) and Brandon Marsh (19) eclipsed that total.
Edge: Phillies
Infield
The Mets middle-infield tandem of Lindor (even with a bad back) and Jose Iglesias is one of the best in baseball and beats Turner and Stott.
The Phillies have the advantages at the corners, though, where Bohm is a solid third baseman and Harper has adjusted well to first.
Edge: Even
Outfield: Hitters looking for hits? Try right field.
Starling Marte has lost at least a step after several lower-body injuries, and Nick Castellanos is a DH hiding in right.
Elsewhere the Mets and Phillies match up roughly evenly, with Brandon Nimmo and Marsh (or Austin Hays) solid in left and Tyrone Taylor (plus a late-game Harrison Bader) and Rojas above-average center fielders.
Edge: Even
Bench
Both clubs emphasize flexibility and defense over a powerful bench bat, though whoever does not start between Jesse Winker and J.D. Martinez is a threat, as is platoon outfielder Hays.
Bader is valuable late in games in the Mets outfield, similar to Edmundo Sosa’s excellent defense anywhere on the dirt for Philadelphia.
Edge: Even
On the mound
Rotation
The Mets could argue that their starting group gives them the better chance.
Since Aug. 1, after which Sean Manaea took flight, Jose Quintana turned a corner and David Peterson excelled, the group posted a 3.28 ERA that was fifth best in baseball and far better than the Phillies’ 4.94.
But the Mets will be rolling the dice with Senga in Game 1 and unable to unleash their ace, Manaea, until at least Game 3.
The Phillies were able to plot out using Zack Wheeler and Cristopher Sanchez to begin the series, a strong 1-2 punch.
Edge: Phillies
Bullpen
The Phillies added closer Carlos Estevez (combined season ERA of 2.45) to an already high-octane bullpen at the trade deadline, joining a core that includes Jeff Hoffman (2.17), Matt Strahm (1.87) and Orion Kerkering (2.29).
The Mets unit has not been the weakness it was in spurts during the season, but there are still issues getting the ball to Edwin Diaz.
Edge: Phillies
Manager
The Mets could not have asked for more from Carlos Mendoza, a first-year major league manager who has kept the team together on several occasions when it could have splintered.
Still, we’ll opt for the experience of Thomson, who won the NL pennant in 2022.
Edge: Phillies
Intangibles
There are plenty of categories to argue about in this breakdown, but this one is not much of a debate. The Mets are the undisputed world champions in intangibles in a season that has included “OMG,” Grimace and now the Playoff Pumpkin.
Edge: Mets
Series predictions
Jon Heyman
Mets in 5
Why stop believing now?
Dan Martin
Mets in 5
The Mets reached the NLCS in 2006 and again nine years later, in 2015. Maybe 2024 is their next trip in what’s already been an unpredictable postseason.
Mike Puma
Mets in 5
The Mets are riding the wave and should enjoy it for at least another playoff round.
Mark W. Sanchez
Phillies in 5
The grind and the depleted arms and Francisco Lindor’s back have to catch up to the Mets at some point, right?
Joel Sherman
Mets in 5
The Phillies have the NL’s best roster. The Mets have something inexplicable going.
Mike Vaccaro
Phillies in 5
The crowds are going to be deafening, both towns, and it’ll be tough to break serve, and that’s the only reason to like Philly by a hair, because Game 5 will be at Citizens Bank Park.