NEW YORK -- Terry Francona is taking the blame for Boston's pitiful play. His players disagree.
One thing everyone can agree on. The Red Sox are running out of time to stop a September slide that could leave them out of the playoffs.
Bumbling Boston lost yet again, with A.J. Burnett making his most impressive start in nearly three months and Jorge Posada hitting a two-run homer that led the New York Yankees to a 6-2 victory in the opener of Sunday's day-night doubleheader.
Boston's AL wild-card lead was cut to a half-game over Tampa Bay, which beat Toronto 5-2. What was a runaway nine-game advantage heading into play on Sept. 4 would be completely gone by the end of Sunday if the Yankees swept.
"When it doesn't go right it's my responsibility," Francona said after his team lost its fourth straight and seventh in eight games.
Not so, said David Ortiz.
"It's all of us, we're all to blame," Ortiz said.
Boston was counting on John Lackey in the nightcap. He was 0-3 with a 9.12 ERA in previous five starts.
The Red Sox at 5-18 (.217) are on track for their worst September since going 4-18 (.182) in 1926, according to STATS LLC. Tim Wakefield (7-8) dropped to 1-5 in his last 10 starts.
Derek Jeter had three hits to lift his average to .300 at the end of the game for the first time since April 2. Starting with July 9, the day he reached 3,000 hits, he is batting .346 following a .257 start.
"I'm not playing for a batting average," Jeter said. I'm playing to try to stay sharp for the playoffs."
New York improved to 6-1 on its final regular-season homestand. Having secured home-field advantage throughout the AL playoffs, the Yankees will open the division series at Yankee Stadium on Friday night.
Sloppy in the field again, the Red Sox fell behind early for the second straight day. Catcher Jarrod Saltalamacchia had an error and a passed ball in a two-run first inning. In the fifth, he had the ball kicked out of his mitt by Jeter, who was trying to score from second base on Alex Rodriguez's single. Jeter reached second on left fielder's Carl Crawford's fielding error.
Boston has committed 16 errors in the last 11 games. The Yankees are 6-11 against Red Sox this season but have won four of last five.
Wakefield pitched four-plus innings, giving up five runs -- three earned -- five hits and five walks. The 45-year-old was making his 627th and possibly last appearance for the Red Sox.
Burnett (11-11) allowed five hits -- three to Jacoby Ellsbury -- and two runs in 7 2/3 innings, his first outing of more than six innings since he went eight on July 29. He was 0-4 in his 10 previous starts against Boston but was in control throughout this one.
David Robertson got four outs to finish, twice stranding a runner on second. Hitters are 0 for their last 22 against him with runners on base, according to STATS.
Two of Ellsbury's hits were homers, giving him 30 for the season and making him the first player in Red Sox history to have at least 30 homers and 30 stolen bases in a season. The two RBIs gave the leadoff batter 100.
"It's not the best time, but I should brag about it," Francona said. "That's an amazing feat."
Batting fourth for the first time since 2009 because of his experience against Wakefield, Posada connected in the third inning for his fifth homer against the knuckleballer. The 40-year-old with a diminished role this year hit cleanup for the first time in two years and was given a curtain call on the last day of New York's regular-season home schedule.
Brett Gardner opened the Yankees' first with a bunt single and stole a base, drawing a wild throw from Saltalamacchia. Jeter bunted safely and Gardner moved up.
Gardner scored when Saltalamacchia fumbled the ball for an error as he tried pull it out of his oversized mitt and make a quick throw with Jeter stealing second.
After Rodriguez grounded out, Jeter advanced to third on a passed ball. Saltamacchia had a shot at nailing Jeter at third but his throw was wide of the base. Jeter scored on a wild pitch from Wakefield.
"It's frustrating," Wakefield said in a nearly silent clubhouse. "We can't seem to catch a break. Certain things happen in an inning and it snowballs from there."
Red Sox RHP Clay Buchholz, who hasn't pitched since June 16 because of a stress fracture in his lower back, will pitch an inning for Boston's instructional league at Fort Myers, Fla., on Monday. If all goes well he could pitch an inning or two Wednesday at Baltimore. ... Red Sox reliever Scott Atchison tweaked his right groin while warming up for the eighth and had to leave the game.