WASHINGTON - Three consecutive bullpen blowups by the majors’ losingest team pushed perennially positive Manny Acta to the breaking point.

After watching the Florida Marlins again shred his relievers in a 7-4 victory Sunday, the Washington Nationals manager promised—and then swiftly delivered—an in-season overhaul.

“I think it’s embarrassing. I think it’s unacceptable. I think our fans have every right to be mad like we are right now,” Acta said. “We’re going to have a brand-new bullpen tomorrow, and if those guys who come in don’t get it done, we’re going to continue getting guys out of here.”

The Nationals made a flurry of postgame moves, reconstructing their ineffective relief corps—which had a 6.48 ERA in 41 2-3 innings—and getting ready for top pitching prospect Jordan Zimmermann to make his first big league start Monday against Atlanta.

Right-hander Steven Shell and left-hander Wil Ledezma were designated for assignment, and right-hander Saul Rivera and catcher Josh Bard optioned to Triple-A Syracuse. The team plans to purchase the contract of right-hander Kip Wells and recall right-handers Jason Bergmann and Garrett Mock.

“It’s unacceptable to perform the way the bullpen’s performed. It shows the incredible strain it’s put on the whole ballclub,” said Nationals vice president Mike Rizzo.

The loss followed a familiar pattern, with the Marlins’ Cody Ross hitting the tying homer in the eighth inning and adding a three-run double in the ninth.

Emilio Bonifacio led off the deciding inning by drawing a walk off Rivera (0-3), and John Baker followed with a double into the gap in left-center. After Hanley Ramirez struck out, Ross Gload was walked intentionally Dan Uggla struck out and Jeremy Hermida walked on a 3-2 pitch.

Ross ripped a double to right-center, clearing the bases and giving him five RBIs while sending Florida to 6-0 on the road with its fourth comeback victory.

“When we’re down, nobody panics,” Ross said. “We have a feeling we’re going to win. It’s just a matter of time. That’s the way we’ve approached it the last week or so and it’s kind of paid off for us.”

Rivera was pressed into service as Sunday’s closer because Joel Hanrahan, who had blown saves in two straight weekend outings, and Joe Beimel had pitched three straight days.

Baker had two RBIs for the Marlins, who are 11-1 and own the best record in the majors. At 1-10, Washington has the worst mark.

“It’s not just one guy getting the job done. Multiple people are capable of getting the job done,” Uggla said. “Whether it’s Wes Helms coming off the bench getting a pinch hit, Cody Ross, Hermida, whomever. It’s not always going to be the guys you think its going to be.”

Leo Nunez (2-0) worked the eighth and Matt Lindstrom pitched the ninth for his third save.

Washington loaded the bases in the first but could only grab a 2-0 lead on singles by Elijah Dukes and Austin Kearns, and Baker’s two-out RBI double cut the lead in half in the third.

The Nationals knocked Chris Volstad from the game in the fifth when Adam Dunn drew a leadoff walk, went to third on a one-out single by Kearns, and eventually scored on Jesus Flores’ single off reliever Hayden Penn.

Nationals starter Daniel Cabrera departed after giving up a leadoff double to Ramirez and walking Gload in the sixth. Shell relieved, loaded the bases by walking Hermida with one out, then allowed Ross’ RBI single that made it 3-2.

Cabrera allowed two runs on three hits and four walks.

The Marlins missed a chance to go ahead after Ross’ homer in the eighth. Right fielder Kearns misplayed pinch hitter Helms’ sinking liner into a double. Alfredo Amezaga, who had reached on an infield single, tried to score but was cut down at the plate—after missing home on his slide and being tagged out by Flores while trying to dance his way back.

Ryan Zimmerman tied the game in the bottom of the eighth on a run-scoring fielder’s choice.