"I left some pitches up and it cost me," Kendrick said. "I didn't give our team a chance. I didn't do my job. They didn't miss the mistakes, and hit two pitches that were out over the plate. That's costly."
Drew, among the most disliked players by Phillies fans, collected four hits, tying his career high. He delivered the more costly of Boston's two first-inning home runs, a three-run shot to right-center.
Four pitches later, Mike Lowell gave the Red Sox their ninth back-to-back home run combination this season. The Phillies answered with a run in the first off Justin Masterson, but the rookie would survive five innings, allowing two runs on four hits.
After a 12-2 stretch that included an 8-2 homestand and a sweep of Atlanta at Turner Field, Philadelphia has gone 3-6 in its past nine games, losing two of three in Florida and St. Louis, and at home against Boston.
The Phillies remain 10 games above .500 and in first place in the National League East.
"That's the good thing," Ryan Howard said. "We've lost three series in a row. But we've played three tough teams. That's not too shabby. We're still in first place. It's still the first half of the season. There's a lot of baseball to be played."
Trailing, 4-0, after one inning and 7-1 by the fifth, there was still plenty of game left, and the Phillies found some offensive spurts. They scored a run in the fifth when Jimmy Rollins laced a one-out single. With runners on second and third, Shane Victorino popped to third and Chase Utley grounded hard to Sean Casey.
The seventh provided a chance at redemption for both. With two runs already in and two more runners on base, Victorino and Utley had a chance to completely erase a five-run deficit that existed at the inning's start.
Victorino again popped out, and Utley fell behind 0-2 before flying to left. That extended his slump to 0-for-20.
"This is why baseball can be frustrating," Utley said. "It is a game of failure, and you have to learn how to deal with that failure."
The season will resume Friday, after the Phillies take a needed day off before hosting the Los Angeles Angels of Anaheim, another first-place team from the American League.
"A day off in a 162-game season is always good." said Howard, who drove in the first run with a single.
The Red Sox took the series without David Ortiz or Kevin Youkilis. They didn't have Manny Ramirez for the series finale, but the World Series champions found a way.
They did it mostly by staying patient and forcing Kendrick to elevate his pitches, snapping the second-year righty's personal five-game winning streak. The Phillies fell to 11-4 in his 15 starts.
"They were patient," manager Charlie Manuel said. "I felt like they dominated the World Series because their hitters are patient. Patience pays off. [Kendrick] got two balls up and they hurt him."