The Giants showcased their offensive resiliency by staging a last-ditch rally in the ninth inning, but it wasn’t enough to overcome a slew of defensive miscues in a 6-4 loss to the Astros in Monday night’s series opener at Minute Maid Park.

Trailing 6-1 in the ninth, the Giants rallied for three runs on an RBI double by Donovan Solano and a two-run single by Brandon Crawford. Austin Slater singled to bring the potential go-ahead run to the plate with two outs, but Ryan Pressly induced a flyout from Evan Longoria to end the game and seal the Giants’ seventh loss in their last nine games.

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Shaky defense continued to be a troubling trend for San Francisco (7-11), which committed three errors on Monday to bring its season total to 21 through 18 games, the most in the Majors. Two of those mistakes came during an ugly third inning, allowing the Astros to score four runs and seize an early 5-0 lead.

“As a team, I think the fewer mistakes we make, the quicker we can clean up these mistakes, the more likely it is that those comebacks turn into wins and not just valiant efforts,” manager Gabe Kapler said. “On the offensive side, to kind of put that together does show some resilience. I think it’s worth pointing that out. There’s no question if we make fewer mistakes, we’re going to convert those into opportunities to compete late in games.”

The Giants were shut down for most of the night by Houston right-hander Lance McCullers Jr., who held the Giants hitless through six innings before Solano broke up the no-no bid with a one-out double down the left-field line in the seventh. Slater later put the Giants on the board with his third home run of the year, a solo shot off right-hander Josh James in the eighth.

Solano’s pair of doubles extended the longest active hit streak in the Majors to a career-high 15 games, but his offensive feats were overshadowed by his two errors, both of which cost rookie Logan Webb.

Webb was charged with five runs (two earned) over 3 1/3 innings in his fourth start of the year, but he pitched better than his final line indicated. The 23-year-old right-hander was let down by his defense in a 36-pitch third, and the Astros capitalized.

“I wish I could have gone longer, for sure,” Webb said. “That’s the game. Things happen, but I also wasn’t as efficient as I wanted to be.”

José Altuve ignited Houston’s big inning by bouncing a one-out single to the left of Solano, who started at third base in place of Evan Longoria on Monday night. Josh Reddick then appeared to ground out, but he was awarded first base after Chadwick Tromp was called on catcher interference.

It was the fourth catcher interference of the season for the Giants, an alarming sum considering Buster Posey has committed three such errors over his 11 seasons in the Majors. Posey elected to sit out the 2020 season after adopting twin girls who were born premature, leaving two rookies -- Tromp and Tyler Heineman -- to split the catching duties for San Francisco.

Kapler explained that Altuve had taken off for second base on the play, prompting Tromp to reach for the ball a little prematurely so he could try to get a throw off.

"My momentum took me to the ball, and I think that combined with Reddick -- I think he has like a long swing -- I think those two played a factor," Tromp said. "Bad timing. I felt horrible, but that's just kind of what happened.”

Webb subsequently walked Alex Bregman to load the bases for Michael Brantley, who flared a two-run double to left field that landed just inside the foul line. The next batter, Yuli Gurriel, tapped a grounder to the left side that was fielded by Solano. But Solano made an errant throw to the plate that eluded Tromp and hit Bregman on the back as he scored, extending the Astros’ lead to 4-0.

“Obviously, if he had to do it all over again, he would attempt to make that throw a little closer to Trompy’s throwing arm, to the first-base side of that play,” Kapler said. “I think at that point, we have a good chance to get the runner at the plate. I thought it was a good decision, it just wasn’t executed.”

Carlos Correa drove in another run by beating out a potential double-play ball before Webb finally coaxed a groundout from Kyle Tucker to end the inning. He came back out for the fourth and opened the inning with a strikeout, but Solano proceeded to misplay a grounder off the bat of Myles Straw for his second error, hastening Webb’s exit at 81 pitches.

“He did a really good job of maintaining composure throughout the game even though we had a couple of defensive miscues and a couple of cheap hits,” Tromp said. “I think he did good. I think he’s on the right path. He’s been good for us. I think he’s going to be really good for us in the future as well.”