Cain is the leader of the pitching staff here -- the elder statesman, if only just barely, of a group that represents equal parts youth and talent. He is not the ace -- that honor goes to Tim Lincecum. He does not have the most future potential -- Madison Bumgarner does. Nor does he have the most electric stuff -- Lincecum, Bumgarner and Jonathan Sanchez might all have him beat in that department.
But Cain was here first. Cain commands the most respect. Cain had the best postseason. And Cain, like the rest of them, will be here for a while.
"It doesn't make sense," he said. "It's unbelievable."
The idea that this group -- all in their 20s, none older than 27 -- will return intact next season is a frightening thought. The Giants proved this season that their rotation can be just as successful as any in the league, from the aging Phillies to the top-heavy Yankees to the vanquished Rangers or anyone else.
And they're only getting better.
"That's what we like to think," Cain said. "We feed off each other. This is just the start, and we want to build off this every year."
They all bring a unique style, from Lincecum's unorthodoxy to Bumgarner's quiet intensity to Sanchez's raw ability. Most importantly, they are all immensely talented at remarkably young ages. And talented young pitching, general managers know, is the game's most valued resource.
With three years still standing between him and free agency, Lincecum should stick around in San Francisco long enough to watch -- and help -- Bumgarner develop into an ace. Cain and Sanchez should be there, too -- they're both under team control until 2013.
All of which means that the four starters in San Francisco's playoff rotation, who combined for an 8-3 record and a 2.18 ERA this October and November, will stick together for at least two more seasons.
Perhaps even two more postseasons.
Perhaps even more.
"It's kind of scary to think about the young arms we've got," said rookie catcher Buster Posey, the group's 21-year-old batterymate.
Though Lincecum may have been the only household name of the bunch heading into October, most around baseball have been aware of the Giants for quite some time. Outfielder Cody Ross, a midseason acquisition, cringed when he thought about facing the Giants' staff as a member of the Marlins.
"I faced these guys and I didn't like facing them," Ross said, recalling his first days with the club. "I went around to every single one of them and said I'm glad I don't have to face you anymore. That's how much I respect them and think that they're that good. They're all young. We've got a good chance for quite a while."
Consider what this group did in the postseason alone. Lincecum, 26, pitched the game of his life in the World Series clincher, striking out 10 Rangers over eight innings of one-run ball. Sanchez, the old man at 27, was dominant in his Division Series start against the Braves. Bumgarner, a 21-year-old, saved the best performance of his young career for Game 4 of the World Series. And Cain? All he did was go unscored upon over 21 1/3 postseason innings.
"It's very exciting," Lincecum said. "Everybody was just doing their part, coming up big in big situations and being the hero that day."
It begs the question, then, of what this group might be able to achieve in the future. Lincecum, Cain and Sanchez are all squarely in their primes. Bumgarner is not even close to his. And this group should stay together for the foreseeable future.
"What are they capable of doing?" reliever Sergio Romo asked, moments after the Giants wrapped up their first World Series title in more than half a century.
"They just showed us."