SEATTLE — If you want to examine all the flaws and fissures that have devalued the San Francisco Giants this season, start with the stuff that you can see with the naked eye.A cheaply built bullpen that doesn’t miss enough bats or throw enough strikes and hasn’t been trustworthy for any stretch. A rotation that has lacked depth. An over-reliance on internal pitching that hasn’t panned out. A shortstop, Willy Adames, who is last in Outs Above Average among his defensive cohort. An offense that ranks No. 4 in batting average and No. 6 in slugging but distantly last in walks, which helps to explain why it is just 24th in runs per game. An inexperienced coaching staff that is on its second third-base coach and is still learning how to mine advantages on the margins.If you want to pull out your jeweler’s loupe and look for smaller stuff, then perhaps Logan Webb makes your list. It’s true, he wasn’t very good in April. He was on the injured list for half of May. His run of making the top six in Cy Young Award balloting probably won’t reach four consecutive seasons.But if your hot take is to cast blame on Webb before anyone else, then the biggest flaw is probably in your own argument.Before his aching knee required a rest in May, Webb had made 156 starts without missing a turn — an ironman run that began in 2021 when he established himself as the surprising ace of a 107-win team. His durability and efficiency allowed the Giants to get away with so many other deficiencies on the pitching side. Webb propped up the rotation in 2023 when the Giants used openers and piggybacked starters for months at a time. He provided a deep start or a complete game on so many occasions when the trusted arms in the bullpen were on fumes. And whenever he lost a game while receiving run support that was as satisfying as tweezer food, which was often, he’d respond to reporters by either holding his tongue or falling on his sword.Even on those occasions when Webb coughed up a late lead or got hit around early, all the good grace he’d already earned couldn’t be discounted.MLB cracks down on using AI in dugoutsAll the while, Webb had to swallow frustration as if it were a competition at Coney Island. He wanted nothing more than to be a part of a playoff team over the past four seasons while the Giants failed to escape the gravitational pull of the .500 mark. Then came this season, which burned up on reentry.When Webb allowed some of that frustration to get the better of him last week, lashing out at a KNBR producer’s critical post on a social media platform, he did himself no favors. The criticism was a bad argument, which should matter, but that’s not the media ecosystem in which we live. When you create conditions for certain outlets to do brisk business by posting a “Logan Webb lashes out” headline, everything else tends to get lost.When the non-story got aggregated and amplified, Webb responded by deleting his Twitter/X account. Not out of embarrassment or as a penance. He simply came to view it as one more potential source of frustration that he didn’t need.There remains enough of that frustration to process between the lines. Webb was brilliant Saturday night in his first start after the All-Star break, holding the Seattle Mariners to one hit while taking a shutout into the seventh inning, but it all came undone in a span of four batters. Webb hit Randy Arozarena with a two-strike pitch, he walked Josh Naylor on four pitches, and then he threw a slider into the swing of lefty-hitting Cole Young that resulted in a tying three-run home run.The Giants couldn’t score their placed runner in the 10th inning, and the Mariners did. In what should’ve been a pitch-around situation, Dylan Smith’s slider caught too much of the plate, and Julio Rodríguez lofted a sacrifice fly as Seattle rallied for a 4-3 victory at T-Mobile Park.It was the seventh time the Giants have been walked off on the road. Most notably, the loss snapped the Giants’ modest three-game winning streak. They’re 0-6 when trying to achieve a fourth consecutive victory.Just last week, Webb commented that the Giants’ inability to sustain momentum — they haven’t swept a series all year — is among what’s frustrated him the most this season. After losing a three-run lead on one pitch Saturday, he didn’t have to reach far for his scabbard.“I feel like I’ve preached that, I’ve talked about it, and I’m the d—head that messed it up,” Webb said. “So yeah. Should’ve won. Should be our fourth win today. That’s a momentum killer.”Before Young’s ball cleared the fence, the Giants had held the Mariners to three hits over 15 2/3 scoreless innings in the series. Webb started the seventh with a manageable pitch count and appeared primed to go the distance.The Giants took a lead against tough right-hander Bryan Woo with an unearned run in the third inning, when center fielder Luke Raley bobbled Bryce Eldridge’s single and third-base coach Gary Pettis alertly waved Drew Gilbert to the plate. Rafael Devers and Adames added solo home runs in the sixth inning to continue what’s been a promising team-wide power surge.Devers muscled his homer inside the left-field pole, and for half a minute, everyone but the umpiring crew appeared to realize it was gone. Devers jogged up the first-base line and used both hands to tap his head frantically as if it were a bongo drum while imploring umpires to review the play. After a brief conference, the home run was signaled and Devers rounded the bases.For all the talk about the trade deadline and underwater contracts, Devers is finding his level after a miserable April. He has better than a .900 OPS since the start of May, he’s second in the major leagues in doubles, and after slugging 18 home runs over his last 66 games, he’s on pace to hit 33 this season.Rafael Devers, congratulated by third-base coach Gary Pettis after he hit a home run in the sixth inning, has come on after a rough start to the season. (Stephen Brashear / Imagn Images)“When he uses his hands, it’s not only really effective but it’s a pretty swing to look at,” Giants manager Tony Vitello said. “That ball going out down the line shows you, all’s he’s got to do is get it anywhere on the barrel and it can go.”Webb had all the ingredients he needed to carry the Giants the rest of the way. But the lid remained on the peach basket. That fourth victory proved elusive once again.“I thought the team played great today,” Webb said. “This game’s on me. I can’t let that happen. You get three (runs) off one of the better pitchers in baseball, you’re up 3-0 in the seventh inning, you gotta find a way to win that game, and I put us in a bad spot. It’s hard to score runs against this team to begin with, and when you get a lead like that, you gotta keep it.“So plain and simple, it’s on me. I messed this one up.”Webb displayed confidence in his sweeping slider all game. He threw the pitch 22 times, his second most in a start this season, and wanted to start it away against Young. The pitch was below the strike zone but directly into the sweet spot for a left-handed hitter looking to launch.“It just kind of backed up,” Webb said. “It had a weird shape compared to all the ones I’d threw. Just not a good pitch. (Hitting Arozarena), that’s unacceptable. You get a guy 0-2 and … that’s something I try to preach with the younger guys is to be in attack mode, especially if you’re winning the game.”Both managers were pressed to make decisions in the 10th inning. Mariners manager Dan Wilson made a curious one, issuing a two-out intentional walk to Casey Schmitt to set up a left-on-left matchup between José Ferrer and Devers. Perhaps Wilson hadn’t noticed that Schmitt has walked eight times all season and might have gotten himself out in a pitch-around situation. Ferrer allowed Wilson to escape criticism when he got Devers to chase a two-strike pitch in the dirt.Vitello’s back was against the wall after the Mariners started their inning with a sacrifice bunt that moved placed runner Victor Robles to third base. Smith pitched to J.P. Crawford and established count leverage before walking him. With lefty hitting Dominic Canzone on deck, it wasn’t a bad gamble to let Smith pitch to Rodríguez. But the Mariners’ designated hitter was playing in his first game after missing nearly two weeks on the concussion list, and has been known to expand the zone, so he probably shouldn’t have seen a strike. Smith threw two pitches that caught a portion of the plate, and Rodriguez did enough with the second one to snap the Giants’ momentum.“Momentum is an interesting topic in general,” Vitello said. “You can’t touch it. Does it exist? Yeah, it definitely does. … To me, momentum is about just stacking positives on top of positives, whether they’re at-bats or pitches, or just how you show up to the park every day. Big-league life is fun, but it’s also an incredible challenge because you get punched, no matter how good you are, about as much as you punch, if not more.”Nobody understands that better than the ace of the Giants’ staff.