ST. LOUIS (Interstat) — A taut pitchers’ duel between Eduardo Rodriguez and Kyle Leahy dissolved into a sudden offensive explosion in the ninth inning Tuesday night, as the Arizona Diamondbacks scored four times in the top half and then survived a three-run rally by the St. Louis Cardinals to win 4-3 at Busch Stadium.

The game was scoreless through eight innings, with both starters throwing zeros against lineups that had struggled for traction. Rodriguez, who entered with a 5-4 record, worked 6 2/3 innings, allowing three hits and striking out five. He walked two and did not allow a runner past second base. Leahy matched him pitch for pitch over 6 1/3 innings, giving up three hits and three strikeouts while issuing one walk. The bullpens on both sides also held firm until the ninth.

Arizona, which had lost the series opener 3-2 the previous night, broke the deadlock against St. Louis reliever Matt Svanson, who entered with a 2-1 record. After Corbin Carroll struck out to start the inning, Gabriel Moreno singled to right. Pavin Smith walked, bringing up Nolan Arenado. Arenado delivered a sharp line-drive double to left field that scored Moreno and sent pinch runner Ildemaro Vargas to third. Lourdes Gurriel Jr. then lined a single to center field that plated Vargas and Arenado, giving the Diamondbacks a 3-0 lead. A groundout by LuJames Groover moved another pinch runner, Jorge Barrosa, to third, and after Tommy Troy walked and Ketel Marte walked to load the bases, Geraldo Perdomo flew out to left. But the damage had been done: Arizona had scored four runs on three hits in the inning, a burst that would prove just enough.

St. Louis did not go quietly. In the bottom of the ninth, Lars Nootbaar led off with a double to center field that was deflected by left fielder Tommy Troy. Nathan Church struck out, but José Fermín singled to left, putting runners at the corners. Alec Burleson then ripped a double to right that scored Nootbaar and moved Fermín to third. Blaze Jordan followed with a sacrifice fly to right that brought home Fermín, cutting the deficit to 4-2. Jimmy Crooks kept the Cardinals alive with a sharp single to right that scored Burleson, making it 4-3. With the tying run on first, JJ Wetherholt struck out swinging to end the game.

Kevin Ginkel, who pitched a scoreless eighth inning with one strikeout, earned the victory. Ginkel improved to 3-2 on the season. Brandyn Garcia recorded the final out of the ninth, striking out Wetherholt to earn his first save of the year. Svanson took the loss, falling to 2-2.

Rodriguez had been sharp in his recent outings, including a win over the Los Angeles Angels on June 17 in which he threw seven innings of one-run ball, and a win at Cincinnati on June 12 despite a shortened start due to injury. His performance Tuesday marked his third consecutive quality start. Leahy, meanwhile, continued his solid season for St. Louis, lowering his ERA with six-plus innings of shutout ball.

The Diamondbacks finished with six hits overall, two of them by Gurriel, who drove in two runs. Arenado doubled and drove in a run. Ketel Marte doubled in the first inning but was left stranded. For St. Louis, Lars Nootbaar went 2 for 3 with a walk and a double. Alec Burleson had a double and an RBI. The Cardinals totaled seven hits.

Arizona improved to 40-39, while St. Louis dropped to 42-35. The game attracted a crowd of 23,560 and lasted 2 hours, 52 minutes.

The two teams meet again Wednesday in the third game of this four-game series. Arizona then travels to Tampa Bay for three games, while St. Louis returns home to face the Miami Marlins.

Interstat’s game simulator had projected a final score of St. Louis Cardinals 5, Arizona Diamondbacks 4. Interstat’s ELO system gave St. Louis a 53.60 percent probability to win. Arizona had been installed as a pregame favorite with a spread of -1.5. The total of 7 went over the over/under line of 8.5.