PHOENIX — Zac Gallen gave the Arizona Diamondbacks a quality start, but the two home runs he surrendered on Monday at Chase Field were the difference in a 3-1 loss to the Cleveland Guardians.

Guardians first baseman C.J. Kayfus was a thorn in Gallen’s side, as he hit a solo homer off a 2-1 count in the second inning.

Kayfus later hit the single that preempted a deep shot from second baseman Brayan Rocchio in the fifth inning, giving Cleveland the only three runs it scored.

Gallen said postgame it’s been frustrating to be bitten by the “homer bug” this season. He’s now given up 26 home runs in 26 starts.

“Ultimately it just comes down to executing,” the pitcher said. “(About) 88, 85 pitches, I threw pretty well. It’s just two pitches that kind of decided the game.”

Gallen allowed five hits and no walks in his six innings, keeping the Guardians’ offense mostly in check outside of the long ball.

“You look at Zac’s line score and it’s a quality start. … On a day where we score six runs, we’re talking about how good Zac pitched,” manager Torey Lovullo said postgame. “He went out there and did his job and kept us in the game.”

He was replaced by John Curtiss, who had 1-2-3 innings in the seventh and eighth. Kyle Backhus had one of his own in the ninth.

Arizona got on the board in the bottom of the ninth when Geraldo Perdomo shot his third triple of the season into the right-field corner, scoring Blaze Alexander, who had just worked a walk.

Alexander’s approach was a highlight for Lovullo, as the third baseman went 0-for-2 at the plate but walked twice.

“Those are the things we preach a lot,” Lovullo said. “You’re not gonna be able to get four hits every night, but (if) you’re able to survey the strike zone and check off of pitches and get on via walk, you’re gonna help out the guy in back of you have a more successful at-bat as well.”

With two outs already on the board, Ketel Marte waved at a ball above the zone and struck out to end the game.

Diamondbacks miss chances to respond

Corbin Carroll, in the sixth inning and right after Gallen exited, knocked a ball off his front foot for a foul and had to be looked out, but he remained in the at-bat for a base hit that Rocchio had a chance at corralling.

Lourdes Gurriel Jr. followed with a hit of his own, and that’s when Cleveland swapped starter Gavin Williams for Erik Sabrowski. Williams had given up just four hits and one walk in 5.1 scoreless innings.

By this point, Carroll was at third as the first Diamondback to get that far, and his fate was left up to pinch hitters Tyler Locklear and Ildemaro Vargas. The pair struck out and grounded out, respectively, to end the inning.

Later, Marte doubled down the left-field line to lead off the eighth, but a Locklear walk provided the only baserunner that followed.

“Tough to build innings today,” Lovullo said. “We did a couple times, created some traffic early with some walks … we did that and just couldn’t get that big hit.”

Cleveland made some outstanding defensive plays earlier in the third inning to help keep Arizona off the board, including diving plays by Rocchio and center fielder Daniel Schneemann.

The Guardians nearly executed a double play on Rocchio’s awkward toss to second for a first out before Marte just beat the throw to first to keep it to one.

Up next for D-backs

The series continues Tuesday at Chase Field when Arizona will throw Eduardo Rodriguez (5-7, 5.40 ERA) against Cleveland’s Tanner Bibee (9-9, 4.54 ERA).

Rodriguez is coming off his best start as a Diamondback, a seven-inning, one-run performance in a win over the Colorado Rockies on Aug. 14.

Catch first pitch at 6:40 p.m. MST on 98.7 and the Arizona Sports app.