But the Red Sox couldn't get anything going against Washington starter Gio Gonzalez and fell, 4-2, at Fenway Park in the second game of a three-game series.
Jarrod Saltalamacchia scorched a two-run single in the seventh inning once Gonzalez was out of the game, but that was it for the Sox as they lost for the fifth time in their last six games.
For the second time in as many nights, a Nationals starter held the Red Sox in check. Gonzalez allowed two runs on three hits in 6 1/3 innings. He struck out five and walked two. On Friday, Stephen Strasburg struck out 13 in six innings as Boston lost, 7-4.
"The last two guys were pretty darn good," said Dustin Pedroia. "We've got to come out and find a way to have better at-bats and score runs for our guy."
Matsuzaka hadn't pitched in the Majors since May 16, 2011, vs. the Orioles. Saturday was his eighth career start with at least eight strikeouts and fewer than two walks. He had just one start last season with at least eight strikeouts.
Though he admitted to being quite nervous about his start, Matsuzaka certainly didn't show it on the mound.
The right-hander struck out the first batter he faced, Steve Lombardozzi, on three pitches. Matsuzaka featured a nasty slider and a fastball that hovered in the mid-90s. He struck out two each in the first, third and fifth innings.
"I did feel nervous leading up to this start," he said. "When I was first told I would be starting today's game, every time I would think about the game I would become a little nervous. I felt nerves coming up, especially [in] the bullpen. It was probably the most nervous I've been during my time here in Boston."
Former Red Sox first baseman Adam LaRoche crushed the first pitch he saw from Matsuzaka into the Boston bullpen to lead off the second and give the Nationals a 1-0 lead. From there, Matsuzaka retired the next six batters before getting into a fourth-inning jam.
He walked Nationals phenom Bryce Harper to start the frame. After a single and a strikeout, Michael Morse hit an RBI double to right. Ian Desmond followed with a two-run single, prompting manager Bobby Valentine to visit the mound.
Danny Espinosa ripped a line drive to right field, but Adrian Gonzalez snagged it and doubled up Desmond at first to end the threat.
Still, it was an encouraging outing for Matsuzaka, who struggled at times in eight rehab starts in the Minors.
"The biggest difference was the consistency of my velocity and the command of all my pitches," he said. "But what hurt me most today was that one walk, and that's an area that I wish I could take back."
Aside from the four runs and leadoff walk to Harper, Valentine liked what he saw from Matsuzaka.
"I thought he threw a lot of strikes with all of his pitches, had good offspeed stuff, pretty good command of his fastball, had it moving both ways," Valentine said. "It looked OK. It looked usable. If we can build on that -- eight strikeouts in five innings -- it's pretty good."
Franklin Morales relieved Matsuzaka to start the sixth and retired all nine batters he faced. It was the left-hander's second straight outing of at least three innings. He went 4 1/3 innings on Sunday in Toronto in relief of Daniel Bard, and the Sox are looking at Morales as an emergency starter.
"We're stretching him out a little, he's maintaining his stuff, throwing strikes, changing speeds, doing a very good job," Valentine said. "[We] have to make as many plans as you can. The way our bullpen is set up, I think he has some length in him. I thought he did, now I have a better feeling that he has some length in him. That's good to have."
As for Gonzalez, he allowed one hit through the first four innings, a double by David Ortiz in the second. The Sox didn't get another hit until Pedroia singled in the sixth.
"His ball was moving a lot," Valentine said. "Hard to hit, hard to see."
Pitching in an Interleague game under American League rules at Fenway Park, Gonzalez was just glad he didn't have to step into the batter's box to face Matsuzaka.
"It was good to be catching my breath once in a while to sit on that bench, take a deep breath. I didn't have to worry about hitting, just try to go out there and worry how to pitch," Gonzalez said. "So you learn from it, and it was fun, especially Fenway. It's such a beautiful ballpark and great fans. All you can do is enjoy the moment."
The Sox fell below .500 for the first time since May 27, when they were 23-24.
Jon Lester is scheduled to start in Sunday's series finale as Boston looks to avoid a sweep.