ST. LOUIS (Interstat) — Iván Herrera launched a three-run homer with two outs in the bottom of the 10th inning, capping a back-and-forth thriller and lifting the St. Louis Cardinals to a 9-6 victory over the Pittsburgh Pirates on Tuesday night at Busch Stadium III.

The game was tied at 6 entering the final frame after each team had traded blows and leads for nine innings. The Cardinals, who had squandered a 5-4 lead in the top of the ninth, refused to let the game slip away. With one out in the 10th, Victor Scott II lined a single into left field against Pittsburgh reliever Mason Montgomery. JJ Wetherholt followed with a single to right, putting runners at first and second. After a flyout, Herrera stepped to the plate and crushed a 1-1 pitch over the left-center field wall for his fifth homer of the season, winning the game in walk-off fashion.

The sellout crowd of 22,958 erupted as Herrera rounded the bases. The game, which lasted 3 hours, 1 minute, pushed the Cardinals to 28-19 on the season, while the Pirates fell to 24-24. Montgomery (1-1) took the loss after allowing three runs on three hits in one-third of an inning. George Soriano (2-0) earned the win with a perfect 10th inning, striking out one.

For much of the night, the game was a pitchers’ duel that turned into an offensive slugfest in the middle frames. Pittsburgh starter Mitch Keller worked 5 2/3 innings, allowing four earned runs on four hits while striking out three. He departed after Nolan Gorman’s two-run homer in the sixth gave St. Louis a 5-4 lead. Cardinals starter Matthew Liberatore struck out nine over 4 2/3 innings but surrendered four runs on seven hits and left after a four-run Pittsburgh fifth.

The Pirates, who had been shut out in each of their previous two games, finally broke through in the fifth. Trailing 3-0, they loaded the bases with a single by Brandon Lowe and a single by Jared Triolo. After a flyout and a strikeout, Bryan Reynolds delivered a two-run double to left-center, cutting the deficit to 3-2. Marcell Ozuna walked, and Oneil Cruz followed with a two-run single to right, putting Pittsburgh ahead 4-3. The rally ended on a popout, but the Pirates had seized momentum.

St. Louis answered quickly. In the bottom of the sixth, Alec Burleson was hit by a pitch, and one out later, Gorman crushed a two-run homer to center, his sixth of the season, putting the Cardinals back on top 5-4. Keller’s night ended after that blast, but the bullpen kept the game close.

The Pirates tied the game in the eighth when Burleson homered again, his seventh of the year, a solo shot to right-center off Pittsburgh reliever Evan Sisk. That knotted the score at 6-6 and set the stage for extra innings.

The contest had earlier been scoreless through three innings. St. Louis opened the scoring in the third when Wetherholt launched a two-run homer to center, his ninth, scoring Pedro Pagés, who had walked. The Cardinals added a run in the fourth on a double-play grounder by Gorman that brought home Burleson, making it 3-0.

Pittsburgh’s best chance to take command came in the ninth. With the score tied 6-6, Nick Gonzales singled, and Konnor Griffin was hit by a pitch. Bryan Reynolds was also hit by a pitch, loading the bases. Marcell Ozuna grounded into a double play, but Gonzales scored, putting the Pirates ahead 7-6. Oneil Cruz walked, and Spencer Horwitz singled to right, driving in Griffin to extend the lead to 8-6. But the rally fizzled when Brandon Lowe flied out, leaving the door open for St. Louis.

Burleson’s eighth-inning homer had come with one out, tying the game at 6-6 after the Pirates had taken a 6-5 lead in the top half of the inning. Burleson finished 2-for-3 with a homer and one RBI. Gorman went 1-for-3 with a homer and two RBIs. Wetherholt added two hits, including the early homer, and drove in two. Herrera’s walk-off blast gave him three RBIs on the night, all on one swing.

For Pittsburgh, Keller was solid despite not factoring into the decision. The Pirates bullpen, including Gregory Soto, who struck out three in a scoreless inning of relief, held the Cardinals in check until the 10th. But Montgomery could not find the strike zone when it mattered most.

The game was the first of a three-game series between the National League Central rivals, who had already met four times earlier in the season at PNC Park, with St. Louis sweeping all four games from April 27-30. The Pirates had dropped two straight coming in, both 6-0 shutout losses to the Philadelphia Phillies, and had been outscored 17-3 in their previous three contests. The Cardinals had lost two of three to the Kansas City Royals over the weekend.

Interstat’s game simulator had projected a final score of St. Louis 6, Pittsburgh 3. Interstat’s ELO system gave the Cardinals a 55.30 percent probability to win. Pittsburgh entered as a pregame favorite with a spread of -1.5. The total score of 15 went under the over-under line of 8.