After back-to-back wins in Philadelphia, the Astros now hold a 3-2 lead as the series shifts back to Houston for Game Six on Saturday.
"All these games have been hard fought," Pena told reporters.
"They have a great team. They put together great at-bats. They have great pitching. Great ball clubs win close games.
"Glad we came out on top. We know there's still work to do and we're going to try to finish it off in Houston."
Pena's single up the middle in the first inning plated Jose Altuve but Kyle Schwarber responded with a solo shot to tie the game one day after the Phillies were no-hit by Astros.
Verlander, who was 0-6 in his World Series starts coming into Thursday, pitched his way out of a bases-loaded jam in the second inning by striking out Rhys Hoskins and settled in from there.
Pena pushed Houston out in front again with a solo home run to chase Noah Syndergaard in the fourth and a Yordan Alvarez run-scoring ground out in the eighth increased the Astros lead to 3-1.
But Philly refused to go quietly.
Jean Segura cut the deficit to one run on a line-drive single to right field that scored Nick Castellanos and brought the red-and-white clad Phillies fans to their feet.
But Astros closer Ryan Pressly entered in the eighth and proceeded to strike out an over-eager Brandon Marsh.
Astros first baseman Trey Mancini snared a sharply hit ground ball from Schwarber to end the threat and Pressly sealed the win with help from Chas McCormick, who made a spectacular wall-crashing grab to rob JT Realmuto of an extra base hit in the ninth.
Verlander, who was part of the 2017 Astros championship team, said the people close to him were overjoyed that he had notched his first World Series win, one of the few stats missing from his likely Hall of Fame career.
"I can say I got one," Verlander told reporters.
"My boys, my teammates, my family, they gave me the rookie treatment after the game. They put me in the cart and rolled me in the shower and just dowsed me with all sorts of stuff," he said.
"It was one of the best feelings in my career. Just truly love these guys. I love our team."
