Felix DoubrontBOSTON — Felix Doubront hasn’t been shy about voicing his frustration. Now, the Boston Red Sox have just as much reason to be frustrated.

Doubront, who is unhappy about pitching out of the bullpen rather than starting, laid a stinker in relief Monday, surrendering six earned runs — he also allowed two inherited runners to score — on six hits and two walks over two-thirds of an inning as the Toronto Blue Jays throttled the Red Sox 14-1 at Fenway Park.

Doubront entered in the sixth inning with the Red Sox trailing 5-0. The first three hitters of the inning reached against Clay Buchholz, who also was ineffective, and the hope was that Doubront could go multiple innings for Boston. The lefty instead crumbled as the Blue Jays teed off en route to a nine-run frame.

“Through the first six innings, it was an ugly night from the mound,” Red Sox manager John Farrell said. “The walks issued (by Buchholz) came back to haunt him. … You give up nine runs in the one inning, that’s asking far too much for any offense to come back from.”

Doubront’s ERA rose to 6.07 with the effort, which was nothing short of awful. The left-hander’s ERA over seven relief appearances — all of which have been in mop-up situations — sits at 11.00 (11 earned runs over nine innings). Making matters worse is that the disgruntled southpaw looked disinterested as the Blue Jays crushed the baseball all over Fenway — and the surrounding area in the case of Melky Cabrera’s three-run homer onto Lansdowne Street.

“I don’t think that he’s disinterested. He’s capable of more. We’ve seen that,” Farrell said. “Three of the last four outings out of the bullpen have been very good. Tonight, obviously not the case. On a night when you’re hopeful you’ve got an opportunity to stretch him out a little bit, get multiple innings, that wasn’t the case.”

Several factors played into Doubront’s move to the bullpen, but it all boiled down to performance. Doubront, who spent a month on the disabled list with a shoulder issue, simply was outperformed by other options, including Rubby De La Rosa and Brandon Workman, and the Red Sox made a necessary move. Now, the Red Sox have a pitcher on their roster whose displeasure seemingly is impacting his performance.

“I would hope not, because when you’re a pitcher, regardless of the role you’re in, you’re asked to go out and execute pitches,” Farrell said when asked if there’s a correlation between Doubront’s struggles and his current discontent. “This is still a staff that’s got competition within it. There are others that have moved ahead of him in the rotation, and opportunities present themselves coming out of the bullpen. He’s been effective in the past coming out of the bullpen. If the role is not sitting well and affecting his pitching, then there needs to be a different focus to realizing his potential and his capabilities.”

Doubront’s career with the Red Sox has been a rollercoaster ride, but he has shown flashes of being a valuable pitcher. This season, however, has been somewhat nauseating, and the situation is unlikely to solve itself.

Doubront declined to speak with reporters after the game.