Matt Cain threw 36 pitches on Wednesday afternoon, most of them ineffective. He faced seven batters, walked three of them, allowed hits to two more of them, threw just 18 strikes and got yanked before the San Francisco Giants even batted.

When manager Bruce Bochy walked out to the mound in the top of the first inning to pull Cain, the exasperation must have been felt throughout AT&T Park. It was certainly seen on Cain's face, his hat tilted up high on his forehead, a look of disbelief and maybe confusion, a silent hand-off of the ball to Bochy, the Giants' season encapsulated in his slow trudge to the dugout. What happened?

Giants fans were too nice to boo; they offered a little polite clapping, but maybe they sensed the symbolism of the moment: The Giants' season is over. There will be no back-to-back to titles, no more talk of a baseball dynasty, no deadline deals to improve the team for this season. The Giants are 40-50 after losing 7-2 to the New York Mets, in last place and bad. The Giants just got swept at home by the Mets, haven't won two games in a row since June 19, have lost 19 of their past 24 and have been outscored by 51 runs on the season, 13th-worst in the National League.

As for Cain, the only previous start in his career in which he had pitched less than two innings was a 2009 game in which he left in the second after getting hit with a line drive. The hit that knocked him out in Wednesday's game was John Buck's bases-loaded flare to center to give the Mets a 3-0 lead. But Bochy had seen enough. "He was disappointed to come out, but I had to make the call," Bochy said. "He's fine, but I didn't want it to become an issue. He was going on 40 pitches there and I didn't want to push him through again."

After an inconsistent start to his season, Cain had been pitching better -- a 1.82 ERA over five starts in June -- until he was knocked out in the third inning against the Dodgers on July 5, a game in which he walked four batters. His heat map from Wednesday shows he was again all over the place. While he does normally pitch up in the zone, check all the red outside the strike zone.

This is what it looks like when you walk three of the seven batters you face. ESPN

The confusing part about Cain's season -- he's now 5-6 with a 5.06 ERA and 16 home runs allowed in 112 innings -- is that he has struggled at home (5.94), a place where he usually thrives with his fly-ball repertoire thanks to the deep power alleys at AT&T, and he has especially struggled with runners on base (.553 OPS with the bases empty versus a .949 OPS with runners on). The splits are so extreme that you have to look beyond just saying he has pitched in bad luck and begin to wonder if he's tipping his pitches from the stretch.

One thing about the Giants' season: Can we lay to rest the idea that the "Giants know how to win"? Did they suddenly lose this trait over the winter? Of course not. The Giants were a good team a year ago that turned into a great team in October. This team never had the makings of a dynasty, especially with a rotation relying on a Tim Lincecum comeback and repeat seasons from Barry Zito and Ryan Vogelsong. Cain's issues couldn't have been anticipated, but it's not exactly a surprise that the rotation has struggled.

The offense hasn't been as good as last year, even though Buster Posey is again putting up MVP numbers, Brandon Belt is pretty much Brandon Belt and Brandon Crawford has actually improved. The offense is down from 4.43 runs per game to 3.93, however, because you're going to have trouble scoring enough runs when the supposed two big bats behind Posey have on-base percentages of .304 (Pablo Sandoval) and .307 (Hunter Pence). Nearly as much as the starting rotation, Sandoval and Pence are responsible for the Giants' last-place standing.

Should the Giants sell at the deadline? Pence is a free agent, although the Giants may want to bring him back. He has hit .218/.258/.366 since June 1, not only hurting his trade value but leading to questions about his long-term viability. Veteran second baseman Marco Scutaro, who's hitting .315 with a .367 OBP, could certainly help somebody. He'd be a great fit across the bay in Oakland, as Eric Sogard is more suited to a backup role. Another reason not to deal away any prospects: The Giants have one of the oldest teams in the league. Their average age for batters (weighted by playing time) is exceeded only by the Phillies and Dodgers in the NL; their pitching staff is the oldest in the NL.

The Giants only had to watch Cain's opponent on Wednesday to see the value of youth. Former Giants farmhand Zack Wheeler displayed his lightning fastball with seven innings of three-hit baseball.