The two follow Aaron Cook, who takes Josh Beckett's start on Saturday against the Royals. Cook had just three days of rest between starts. Manager Bobby Valentine admits that the bullpen will be "stressed" Saturday, and expects the situation to remain difficult going forward.
"With Doubront tomorrow we can't really expect a complete game out of, and Daisuke on Monday, there's some pitching concerns right now," Valentine said.
Doubront last pitched Aug. 9 against Cleveland, allowing four runs on seven hits in 4 1/3 innings. It was part of a post-All-Star break slump that prompted talk of shutting down the young lefty. He was eventually placed on the DL with a right knee contusion, but there had also been shoulder fatigue.
Matsuzaka was placed on the DL on July 3 with a right upper trapezius strain. He managed to make just five starts after returning from Tommy John surgery before the newest injury popped up.
Matsuzaka posted a 2.82 ERA in five starts with Triple-A Pawtucket since returning from the neck issue. He has little time to show the organization much before his contract expires. The hope is he is more ready to make a contract push this time than he was when he first returned in June.
"He's a guy we're gonna continue to work with," general manager Ben Cherington said. "He's now toward the end of a full year off after Tommy John surgery so it would be typical of a guy starting to feel like himself. He had a good outing in Triple-A so hoping to see more of that. Haven't talked about anything past this season."