David Ortiz added three hits and also encouraged the Red Sox, shouting at his teammates from second base after a double and later gathering them for a huddle in the dugout.
With the Red Sox in danger of falling into a 3-1 deficit, it was a stroke of good fortune by Gomes -- he was a late addition to the lineup when Shane Victorino's back stiffened up, and was 0 for 9 in the Series before connecting off reliever Seth Maness.
Gomes spread his arms wide as he rounded first base, shouted and twice banged his chest. When he got back to the dugout, a couple of teammates gave Gomes' beard a good tug and Mike Napoli joined in with a hard, two-handed yank.
Along with his pop, Gomes showed off the patience that mark Boston hitters. He drew a 10-pitch walk from Cardinals starter Lance Lynn the previous inning, helping set up Stephen Drew's tying sacrifice fly.
Game 5 is Monday night as Cardinals ace Adam Wainwright faces Jon Lester in a rematch of the opener when Boston romped. It'll be a busy sports day in downtown St. Louis with the NFL matchup between the Rams and Seattle a few blocks away.
Ortiz did more than his share, as usual.
Big Papi singled, doubled and walked his first three times up, making him 7 for 10 in the Series. He'd also reached base in 11 of 15 plate appearances.
Ortiz hollered to the Boston bench when he doubled in the fifth, as if trying to wake up the weak-hitting Red Sox, and later hustled home on Drew's fly to make it 1-all.
Before the sixth, Ortiz gathered his teammates in the dugout and urged them on.
Lynn retired the first two batters in the sixth before Dustin Pedroia singled. Lynn wanted no part of Ortiz and walked on four pitches.
Maness relieved, and Gomes connected on a 2-2 pitch. Maness doubled over near the mound while Gomes circled the bases.
Buchholz pitched a season-low four innings, marking the second straight day a Red Sox starter didn't reach the fifth.
Beltran, already one of the best postseason players ever, improved to 8 for 10 with runners in scoring position this October. The Red Sox committed their sixth error of the Series — Ellsbury has two of them after making only three during the entire regular season.
Even with the Cardinals holding a 2-1 edge, the sellout crowd at Busch Stadium sounded a little quiet at the start. Perhaps the fans were drained by the late-night theatrics Saturday, when an obstruction call gave St. Louis a 5-4 win.
Lynn broke three Boston bats in the early going. Ortiz had the only hit for the Red Sox, an infield single off Lynn's leg. The St. Louis right-hander got Gomes to ground into a double play to erase Ortiz.
Buchholz was dealing with weakness in his right shoulder, and it showed in his velocity. Through three innings, his fastest pitch was clocked at 90 mph.
Yadier Molina kept up his sweet swing, lining a double in the second. That made him 6 for 13 in this matchup and a robust 21 for 57 in his Series career.
Carpenter hit a one-out single in the third and hustled to second when Ellsbury took his time getting to the ball and then mishandled it, the ball skipping off the heel of his glove. Beltran followed with a single up the middle.
The Cardinals said Craig was OK. They were worried about him Saturday night after he re-injured his sprained left foot while scoring the winning run in the ninth inning on that obstruction call.
Link to box score: Boston 4 at St. Louis 2
Link to game discussion at The Cardinal Nation message board
Pickoff ends World Series game for first time ever