NEW YORK -- Before the Mets departed Citi Field on Sept. 22 for the start of a memorable road trip that took them to Atlanta, Milwaukee, Atlanta again, Milwaukee again and finally Philadelphia, both manager Carlos Mendoza and first baseman Pete Alonso were asked about the prospect of that last home game being their final one in Queens this year.

Although the questions were asked in the context of it possibly being Alonso’s last game in a Mets uniform, they applied to everyone. The odds of the Mets qualifying for the postseason, at that point, were solid but not overwhelming. The odds of the Mets qualifying for the playoffs and winning a National League Wild Card Series against the Brewers or Padres seemed immense.

Of course, the Mets not only accomplished both those things, but they also split their first two NL Division Series games in Philadelphia for good measure. As a result, they’ve not only returned home, but they’re guaranteed at least two postseason games at Citi Field.

“We knew it wasn't going to be easy,” Mendoza said Monday, back at Citi for the first time in 15 days. “We had to go through a lot, not only traveling, but playing good teams. We needed to get to the playoffs, then advance and win that Wild Card [Series]. But I always have faith in the guys, in the players.”

Monday, the Mets held an optional workout under a brilliant sunny sky at Citi. Game 3 starting pitcher Sean Manaea and most of the team’s relief pitchers rolled through to play catch. Francisco Lindor, who continues to receive regular treatment on his lower back, also came through the doors. So did Jeff McNeil, who continues to swing a bat daily in hopes of returning for a potential NL Championship Series roster.

Thinking to the future in that way no longer seems so sanguine for these Mets, who have proven their mettle against the best teams in baseball -- something they hadn’t yet done, at least not to the same extent, before leaving home.

“We’ve had to go through a lot of things just to get here,” Manaea said. “At the same time, it’s the belief in each other, this team, this organization -- I don’t think anybody in that clubhouse doubted that for a second. That’s a special thing about this group -- we just keep believing, and we’re here. All we had to do [was] get our foot in the door and let’s see what happens. We’re at that point.”

• Mets 'having the most fun we've ever had' as long & winding road trip ends

The Mets are expecting a sellout crowd for NLDS Game 3 on Tuesday. Game 4 the following night will be a potential clincher for one of the two teams, with all the excitement that comes along with it.

So yes, the Mets managed to make their return to Queens, largely with the same personnel as when they left. Somehow, though, this all seems different.

“Here we are,” was how Mendoza put it. “Back at Citi Field with a tremendous opportunity to win a series and keep going.”