It was a struggle all evening for Peavy, who didn't have a strikeout in five-plus innings. He allowed 10 hits and six runs while failing to protect a 6-3 lead heading to the sixth.
It was a far cry from Peavy's Red Sox debut on Aug. 3, when he allowed just two runs on four hits through seven-plus innings against Arizona.
"I take the blame," Peavy said. "Your offense can't score six runs and you not win a game that you start. I didn't feel good stuff-wise or command-wise. There were a lot of two-strike hits and my stuff just wasn't sharp at all."
Peavy caught a huge break in the fifth when Alex Gordon lined into a double play with two on. On the strength of Mike Napoli's three-run double in the fourth, Boston still had a 6-3 lead and hoped that Peavy would get his second wind in the sixth.
It didn't happen. Kansas City opened the sixth with three consecutive hits, including an RBI single by Alcides Escobar that made it 6-4. Out came Peavy, in came Drake Britton and the Royals' momentum was about to snowball.
Britton got off to an ominous start by walking George Kottaras, a .167 hitter, in a lefty-on-lefty matchup. Miguel Tejada popped out, but David Lough produced a sacrifice fly to right. When Shane Victorino went for the play at the plate and barely missed getting Mike Moustakas, the other runners advanced to second and third. That proved huge moments later when Eric Hosmer laid his bat on a two-strike pitch and rolled a two-run single through the left side against the shift to put the Royals on top 7-6.
"We're taking a three-run lead to the sixth and figure Peavy has probably got that one inning left in him," manager John Farrell said. "But a few pitches up in the strike zone [proved costly]. ... When we mislocated, they made us pay. We just couldn't stop the momentum in the sixth."
Pedro Beato relieved Britton in hopes of keeping it close, but Billy Butler had an RBI double and Justin Maxwell added an RBI single. It marked the first time since May 23 against Cleveland that the Red Sox had surrendered a six-run inning.
"You can tell [the Royals] are playing with confidence," Peavy said. "It was evident tonight."
Boston knocked out Kansas City starter Ervin Santana with nine hits and six runs through 3 2/3 innings, but the Royals' bullpen stemmed the tide and kept the Sox off the scoreboard. The Sox had one brief opening in the eighth when reliever Tim Collins started the inning by walking Jacoby Ellsbury and Victorino. Dustin Pedroia followed with a hard smash toward third that Moustakas turned into a 5-4 double play.
The silver lining for the Red Sox was seeing Napoli reach base four times, including his three-run double in the fourth. But now the Red Sox find themselves needing wins on Saturday and Sunday to salvage a series split.
"Bruce Chen did a great job the first night and tonight was one that kind of got away from us," Pedroia said.
Kansas City manager Ned Yost felt it was poetic justice that the Royals were able to storm back and win on a night when Santana didn't have his best stuff. Santana has been victimized by poor run support on numerous occasions, but the Kansas City offense had his back on Friday.
"Fantastic win," Yost said. "It was a night when Ervin didn't have his command, but the bats picked him up. He has picked us up so many times this year."