Raised in Fort Collins, about an hour north of Denver, he is quite familiar with Coors Field.
"I spent a good part of my life there," the Cardinals lefty said.
Gonzales came back to beat his boyhood favorites on Sunday.
In just his fifth major league start, Gonzales struck out nine and allowed one run over 5 2/3 innings to help the NL Central-leading Cardinals beat the Rockies 4-1 for their third straight win.
The Cardinals held their 3 1-2-game division lead over Pittsburgh. St. Louis has won 13 straight regular-season home games in September and October.
Colorado lost all six games on its just-completed road trip. Third baseman Nolan Arenado left the game soon after bruising his chest diving for a ball in the third inning.
Jhonny Peralta hit a two-run homer to cap a three-run rally in the third inning. It was his team-high 21st homer.
Gonzales (3-2) turned in the finest effort of his career under the pressure of a pennant chase.
"It's great to be in a race, you could feel the intensity out there," Gonzales said. "My number was called and I just tried to focus, go out there and do my job."
Gonzales, the Cardinals' first-round pick in the 2013 draft, gave up two hits over the first five innings and carried a 3-1 lead into the sixth. He surrendered a two-out single to Brandon Barnes before leaving.
"It was a terrific outing," St. Louis manager Mike Matheny said. "We needed that. He really came up big."
Added catcher Yadier Molina, "He stepped up and I'm happy for him."
Gonzales' strikeout total was the most by a Cardinals rookie left-hander since Rick Ankiel fanned 11 in 2000 against Pittsburgh.
Trevor Rosenthal struck out the side in the ninth to pick up his NL-leading 44th save in 49 opportunities. Six St. Louis pitchers combined to fan 16.
Peralta's homer, a 410-foot shot off Jordan Lyles (6-3), broke a 1-all tie and put the Cardinals ahead to stay.
"When I hit it, right away, I knew I hit it good," Peralta said.
Matt Holliday hit an RBI double before Peralta homered. Molina had three hits for St. Louis and scored in the eighth on a wild pitch.
Barnes drove in the Rockies' run with a double in the second.
Lyles gave up three runs on nine hits over six innings.
"I just made a mistake to Peralta and good hitters put good swings on the ball," Lyles said. "He hit it a long way."
Colorado scored just eight runs during the six-game losing streak, three came in the ninth inning of a 5-4 loss to St. Louis on Saturday.
The Cardinals, who are 19-2 in their last 21 home games in September and October, carry plenty of momentum into a three-game series against Milwaukee that begins Tuesday.
"For us, it's a one-game series every night," Matheny said. "That's the way we've got to look at it."
Rockies: 1B Justin Morneau did not start for the second successive game after straining a side muscle in Friday's 5-1 loss.
Cardinals: 1B Matt Adams was held out of the lineup. He sustained a slight oblique muscle pull in Saturday's 5-4 win. He is listed as day-to-day.
Rockies: RHP Christian Bergman (2-3, 4.89) will face Roberto Hernandez (8-11, 4.04) in the opener of a three-game against Los Angeles Dodgers on Monday in Denver. Bergman will be making his eighth major league start.