PHILADELPHIA -- The beauty of Jeremy Peña’s sensational postseason is that the Astros’ newcomer has spent none of it looking over his shoulder, except perhaps while making another terrific defensive play.

In Peña’s mind, the challenge was never to fill someone else’s shoes; it was all about being the best version of himself. Suffice it to say, Peña is succeeding, becoming the first rookie shortstop to homer in the World Series with a go-ahead blast in the Astros' 3-2 victory over the Phillies in Game 5 on Thursday night at Citizens Bank Park. His heroics helped put Houston on the cusp of the second World Series title in franchise history as the series shifts back to Minute Maid Park.

“Once we accomplish our goal, which is to go all the way, then I’ll sit down and reflect on the journey,” Peña said. “But there’s still work to do, and we’ve got to lock it in.”

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Having already brought home hardware as the MVP of the Astros’ American League Championship Series sweep of the Yankees and announced as a Rawlings Gold Glove Award winner this week, Peña continued his showcase into the Fall Classic.

“He’s very confident in himself,” said the Astros’ Alex Bregman. “He’s confident in his bat speed. He trusts his plan and he’s executed really well all postseason. It’s been impressive to watch. He had a little bit of a period where he was chasing late in the season. He’s simplified things. Literally every week that goes by, he just gets better and better.”

Houston grabbed the lead behind Peña’s fourth-inning homer, with the youngster mashing a hanging curveball from Phils starter Noah Syndergaard into the left-field seats.

When did he know it was gone?

“When the umpire signaled home run,” Peña said, laughing. “I hit it, you know, and it felt good off the bat, but I didn't know if it was enough. And I was running normal and then when the umpire signaled, that's when I started jogging.”

As Peña rounded the bases, he pointed his right index finger high toward the sky, offered a “who, me?” shrug to his teammates, then angled his fingers in the shape of a heart -- a message to his mom.

The deep drive gave Peña nine extra-base hits in this postseason, tying the third-most by a rookie in a single postseason behind Houston’s Yuli Gurriel (10 in 2017) and Rays outfielder Randy Arozarena (14 in 2020).

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“Coming in as a rookie at the Major League level isn't ever easy, no matter what,” said Astros starter Justin Verlander, who picked up his first career World Series victory on Thursday. “To step in and try to replace a Carlos Correa on a roster where he was a mainstay and a leader of our team … To step up in the biggest of moments, it's been a lot of fun to watch.”

Peña had more in the tank besides the home run, roping a pair of key singles and contributing a sharp leaping catch to rob Nick Castellanos of a third-inning hit.

“Boy, he's played remarkably well,” Astros manager Dusty Baker said. “He's really carried us for a while here through this postseason, and that's especially tough for a young player, a young shortstop. I'm just glad we have him.”

The future of the Astros at shortstop was a frequently-discussed topic last spring, with uncertainty over how the club would soldier on following Correa’s departure to the Twins in free agency. Those questions aren’t being asked anymore; with Peña, the position appears to be in good hands for years to come.

“You’ve just got to be grateful to be in the position that we're in,” Peña said. “We're in the World Series. That in itself is something special. So I just go out and enjoy it, have fun, play hard, play my game, and then just trust my preparation.”