"That was typical Brett, as far as I'm concerned," Kennedy said. "He's been pitching great."
The hard-throwing southpaw fanned eight, thanks in large part to a devastating slider that was particularly effective against Boston boppers Jason Bay and Kevin Youkilis, who were a combined 0-for-8 with seven strikeouts.
"I mixed and matched early in the count rather than going with my fastball to get to the slider," said Anderson. "They were probably gunning for me a little bit extra after the outing I had last time, so I tried to work the outside part of the plate and hopefully catch them off-guard with the slider."
The A's did most of their damage by sending nine men to the plate in the top of the first before the Red Sox had a chance to take their hacks against the 21-year-old Texan, who allowed just two hits in a 2-0 win at Fenway on July 6.
Kennedy lofted the first pitch of the game from Red Sox starter Brad Penny -- a meaty 94-mph fastball -- into the Green Monster Seats for his eighth homer of the season.
"Penny's a fastball pitcher," Kennedy said. "I was just trying to put a good swing on one."
After the right-hander loaded the bases, Ryan Sweeney beat out a grounder to short that scored Orlando Cabrera, and Rajai Davis belted a fastball off the Monster three batters later for a three-run double.
"Any time you get on the board early, it's big," A's manager Bob Geren said. "[Penny] didn't have his normal command, and fortunately, we were able to jump on him."
"I'll take us scoring five any day," Anderson said.
The Red Sox got three back with one swing of the bat in the bottom half of the inning, when Mike Lowell cleaned out an Anderson slider and drove it well over the towering left-field wall.
Boston would not score another run against the A's youngster, who felt a twinge in his calf after catching a cleat on the mound while throwing a first-inning pitch.
"It didn't hurt or anything," said Anderson, who threw a series of warmup pitches after the incident. "It just felt weird for a second. It didn't affect me at all."
It sure didn't.
"He got very competitive after the [Lowell] home run," Geren said. "You could go one of two ways there. That could make you really refocus, or you could fall apart real easily, and he did the right thing.
"Excluding that first inning, he was outstanding."
The A's neutralized Lowell's long ball with Suzuki's fifth-inning blast and a two-run double from Eric Patterson in the sixth.
The Red Sox pushed runs across in each of the final three innings against Oakland's bullpen, but Andrew Bailey nailed down his 13th save of the season in the ninth by getting J.D. Drew to ground out with the tying runs on base.
Bailey's high-wire act preserved Anderson's second win in as many starts at Fenway Park, a venue where the pitcher has found quite the comfort zone.
"This is a fun place to play," Anderson said. "Regardless of who's here and what's going on, the atmosphere is incredible. You know there's going to be fans, and you get amped up a little bit extra to pitch against these guys.
"It feels like baseball. It's the way it's meant to be, and it's the way it's meant to feel. You go out there and it feels like baseball. I can't really describe it any other than that."