Zac Gallen improved to 3-0 and Christian Walker went 3 for 4 with a run in the Arizona Diamondbacks’ 5-0 victory Sunday over the St. Louis Cardinals at Phoenix.

Arizona, also led by Corbin Carroll’s two RBIs and Jake McCarthy’s 2-for-3 performance, won two of the three games in the series with St. Louis.

McCarthy and Carroll collided near the warning track going for a fly ball hit by Willson Contreras in the top of the sixth. McCarthy made the catch. Carroll did not immediately get to his feet after the play, but both jogged off and continued to play.

The game was scoreless through the first four innings with Opening Day starters on the mound — Gallen for the Diamondbacks and Miles Mikolas for the Cardinals.

Mikolas (1-2) faced the minimum of 12 batters in the first four innings and induced a double play in the bottom of the second after Walker led off the inning with a single.

Walker started the fifth inning with another single and moved to third on Joc Pederson’s double. Jace Peterson then followed with a sacrifice fly to left field, scoring Walker for the first run of the game.

McCarthy doubled in Pederson to give Arizona a 2-0 lead.

After walks to Tucker Barnhart and Ketel Marte loaded the bases, Andre Pallante relieved Mikolas. Mikolas finished up allowing four hits in 4 2/3 innings with three strikeouts and two walks.

Carroll welcomed Pallante with a single to score McCarthy and Barnhart. The five-run rally ended when Marte scored on a Pallante wild pitch.

Gallen allowed four hits in six innings while striking out seven and walking two. Joe Mantiply relieved Gallen to start the seventh inning and did not allow a hit in 1 1/3 innings. He had a strikeout and walk.

Bryce Jarvis pitched a hitless 1 2/3 innings to close the game for the Diamondbacks.

Pallante and Ryan Fernandez did not allow a run in their combined 3 1/3 innings of relief for St. Louis. Fernandez pitched the last 2 1/3 innings and did not allow a hit. He struck out two and walked one.