FOXBOROUGH, Mass. — During the New England Revolution’s six-game winless skid, head coach Brad Friedel has repeatedly spoken about fundamental, avoidable errors on defense. Rarely, however, has a player publicly heaped blame upon himself in the name of accountability.

Antonio Delamea bucked that trend after Saturday’s 3-2 home loss to the Philadelphia Union, when his handball resulted in a penalty kick – and eventual game-winner in the 76th minute – that Fafa Picault slotted home. The head-scratching play zapped all momentum from the Revs’ comeback efforts, and a possible three points quickly turned into zero against a team who jumped ahead of the Revs in the Eastern Conference.

“I just feel like we’re a bunch of guys that don’t take responsibility when it’s necessary,” Delamea told Seth Macomber of the Bent Musket. “I think today can start with me. I messed it up. It’s my fault that we lost this game. I think everyone can be mad at me.”

As the Revs gear up to face D.C. United on Sunday (7:30 pm ET | FS1 — Full TV & streaming info), Delamea’s teammates backed his sentiment. Andrew Farrell called it time to “look in the mirror,” while Teal Bunbury said “everybody needs to be held accountable to themselves.”

Their visibly frustrated comments during a stretch that has procured five of a possible 21 points following the World Cup break. That span has also included two losses and a draw at a normally-resolute Gillette Stadium.

“I’ve always said whenever we’re honest about our mistakes and push on forward, that’s when we can improve,” Jalil Anibaba said. “I’ve always felt that by and large our group has done a decent job of that throughout the course of the season, and Toni has been a huge part of our defense throughout the season. I would only piggyback what he has to say about that, but at the same time no win or loss ever comes down to one player or one play.”

Accountability aside, set pieces have recently undone the Revs. Five straight goals against have come from corner kicks or free kicks: the latter two from the 3-3 tie Aug. 4 vs. Orlando, and then all three vs. Philadelphia.

Otherwise, Friedel said, New England is in good shape defensively. And things could take another step forward with Michael Mancienne slated to start training on Thursday after receiving his P-1 Visa. It’s not yet clear if the experienced center back, signed from Nottingham Forest on a free transfer, could feature vs. D.C.

“We don’t concede many chances [from the run of play],” Friedel said. “A lot of the games when you look at clear-cut, quality chances, teams haven’t created that many. It’s a shame that we’ve been figuring out ways to concede goals, so to speak.”

At this juncture, Diego Fagundez also noted how external solutions aren’t likely to arrive. Unless the Revs sign a free agent before the Sept. 14 roster freeze, they’ll go on a playoff push with the group that will be at training on Thursday.

“After last game, we came into the locker room and said nobody is going to walk into these doors and help us out,” Fagundez said. “We have to make sure we’re all sticking together. It’s the only way.”