"Every at-bat in this game is its own at-bat," the shortstop said. "Whether you're 5-for-5 or 0-for-5, that doesn't help you with that next one. You've got to go up there and get a pitch to hit and do something about it."
With two outs and runners on first and second in the 15th inning, Pennington lined a 1-1 sinker from Scott Rice into left field. As the ball dropped in front of Eric Young Jr., Gerardo Parra dashed home to score the eventual winning run.
The D-backs finish their 10-game eastern road swing 3-7, but with back-to-back wins.
The eventual-winning run didn't incite manic celebration, though. The team was simply exhausted.
"We just wanted the game to end," Pennington said.
He had faith that his bullpen would shut the door, even though twice before it had given back runs that seemed to have won the game.
The first came in the 13th, when Cody Ross walked with the bases loaded to hand the D-backs a 3-2 lead. Anthony Recker answered with a solo home run for the Mets. A Martin Prado flare over the head of Jordany Valdespin at second base handed Arizona another lead in the 14th. This time, Kirk Nieuwenhuis homered in response.
"It's a grind, for sure," D-backs manager Kirk Gibson said. "Of course we got disappointed when we get the lead and they hit the home run, and it's disappointing that you have to reload and understand what's ahead of you.
"Then they hit the second one and you just got to tell yourself, 'We can take it.' You learn a lot about yourself in series like this and days like this."
Rice got two outs to start the 15th, but the D-backs rallied. Parra singled to center. Wil Nieves followed with a single of his own, moving Parra to third.
Then Pennington stepped in. His single to left gave Arizona its third lead of extras, and this time Brad Ziegler shut the door for his first save of the year.
"He's 8-for-11 in extra innings," Gibson said of Pennington, "so he's a good guy to have at the plate."
Pennington's penchant for extra-inning success and Ziegler's first saved capped a strange game and series at Citi Field.
The series, checking in at 16 hours and 40 minutes, was the longest since 1989. The game, which featured among other irregularities a bunt double and an 8-4 fielder's choice, ultimately came down to a middling infielder and a relief pitcher who didn't expect to play.
Ziegler had pitched back-to-back days and wasn't planning on making it three straight. When he got the call, he had to totally flip his mentality to bear down for an arduous 15th.
He walked two of the first three batters to put the tying run at second with one out, but the sidearmer stuck to his M.O. and induced a pair of groundouts to end the game.
"If I'm going to feel pressure, it's not going to matter what happened previously in the game," Ziegler said, "it's the fact that we've got a chance to win this game right now and no matter what happened, I've got to get three outs."
Ziegler said he would've gone one more inning if needed, but after that, a strange day would have just gotten stranger. Pennington, the hero on offense, was next in line to pitch. Nieves would've moved from his spot behind the plate around the infield. Even Patrick Corbin could have gotten in -- as an outfielder.
The big takeaway for Gibson is that his team will never give in, but that's something he's already seen this year. The D-backs played a 16-inning game with the Cardinals on the third day of the season. They played into the 12th four other times and are now 10-3 in extra-inning games this season.
Pennington's been a consistent surprise in those games, delivering a pair of walk-offs already, but he's just become an extension of what Arizona does: like Pennington, it delivers in the close ones.
"This is what we've been all year," Pennington said. "We've been really good in extras, we've been really good late in games because we're going to keep grinding, keep battling and we've got to do that. You're going to play close games in this league. There's too much parity to not."