SAN FRANCISCO -- If you ask Giants manager Gabe Kapler, he firmly believes that recently extended ace Logan Webb has performed far better than the results have indicated.

"He's been great all the way through," Kapler said. "From my perspective, it's like every start has been a competitive, attack-the-strike-zone, get-swings-and-misses, fearless approach."

Webb was a little more critical of his overall body of work following his outing on Thursday afternoon, which saw him drop to 1-5 on the season after the Giants were shut out by the Cardinals, 6-0, in the series finale at Oracle Park.

The loss snapped San Francisco's five-game winning streak, though the Giants went 5-3 against the Mets and the Cardinals to secure their first winning homestand of 2023. As the team heads south for this weekend's two-game set against the Padres in Mexico City, Webb is searching for a way to turn his season around.

"It's very frustrating," Webb said. "I think I lead the league in losses now, so it's not a fun place to be. … I'm not trying to go out there and lose games. My job is just to go out there and put the team in the best position to win, and I haven't been doing that."

Contrary to his self-evaluation, Webb leads the Giants' rotation with three quality starts this season. He allowed two runs on seven hits over 6 2/3 innings on Thursday, extending a six-game streak in which San Francisco starters have allowed two earned runs or fewer.

Striking out seven against one walk, Webb cruised through the Cardinals' order with the exception of two traffic-heavy innings.

Webb got into a jam in the top of the third, loading the bases on two singles and a walk, but he escaped with an emphatic strikeout of Nolan Gorman to end the threat. From there, he retired 10 straight before allowing a solo home run to Alec Burleson with one out in the seventh.

With two runners in scoring position and two outs, Webb nearly got through seven frames in back-to-back starts by getting Tommy Edman to hit a sharp grounder right at second baseman Thairo Estrada. Though the speedy Edman was initially ruled out, the call was overturned upon review, bringing home another Cardinals run and ending Webb's afternoon.

While Webb has looked much more like himself after his first four starts of the season, he continues to be stung by the long ball. The 26-year-old righty has allowed a homer in all but one of his outings this season, totaling seven in six starts. 

Webb is on pace to surpass his single-season career high for home runs allowed -- he gave up 11 home runs in 2022 -- but Kapler believes he will work past these early issues.

"Home runs -- it's just not going to be a thing [for Webb]," Kapler said. "It has been so far, but it's not going to be going forward."

After the Giants showed signs of progress against left-handed pitching in Wednesday night's 7-3 win, they were stymied by a righty the following afternoon. Entering Thursday, San Francisco ranked second in the Majors with an .814 OPS against right-handers -- but the lineup could not get much going against St. Louis veteran Miles Mikolas, who scattered four hits over 6 1/3 frames.

The Giants' best opportunity came in the fifth, when David Villar and Brandon Crawford strung together a pair of singles and LaMonte Wade Jr. walked to load the bases with one out. But Andrew Knizner made a nice play at the plate on Estrada's infield grounder and Mikolas got Joc Pederson to fly out to right, ending the threat.

Webb has not received much run support in the early going, with San Francisco averaging 2.89 runs per nine innings when he's taken the mound this season. The Giants have scored three or fewer runs when he's taken the mound in five of his six starts.

Webb may put the onus on himself, but the Giants know they have to get the bats going for their ace as well.

"If we had seven runs up on the board for him, it looks like a great start and he's probably happy to walk away from it," said catcher Blake Sabol, who went hitless with three strikeouts Thursday. "Logan's a competitor. He really wants to win. He's one of the leaders on this team, so when we lose a game, he's going to try and take some of the blame for that."