Matsuzaka, meanwhile, was sharply focused on his brave new world, which on this day entailed pitching to Barry Bonds with the game on the line. On a day Matsuzaka couldn't afford to give up even one run if he wanted to emerge victorious, he didn't.
By firing seven shutout innings against the Giants, Matsuzaka (three hits, eight strikeouts) lifted the Red Sox to a tight, 1-0 victory in a crisp contest played on a picture-perfect Saturday at Fenway.
"This was the first time I was able to hold the opponent to zero runs and at the same time I was able to protect our slim and precious one-run lead," Matsuzaka said through translator Masa Hoshino. "So, in that sense, I'm very happy with my performance today."
This one meant something to Matsuzaka (8-5, 4.18 ERA) when you consider he had given up two runs in each of his last two starts and lost.
And also because Osamu Higashio, Matsuzaka's manager with the Seibu Lions from 1999-2001, was watching him in the United States for the first time.
"Ultimately, I was able to show [Higashio] what I think was my best performance today," Matsuzaka said. "So I feel that he'll be able to return to Japan happy."
Manny Ramirez put a few smiles on quite a few faces as well, belting a solo shot off Matt Cain in the fourth that proved to be the only hit of substance for either side. Ramirez came into the game 0-for-June in homers, but this shot into the Monster seats ended a 50 at-bat drought.
It wasn't one of Ramirez's most graceful swings, but style didn't count in a tense contest such as this.
"That was a lot of hands and wrists in that swing," said Red Sox manager Terry Francona. "Like maybe only he can do."
Cain (2-7, 3.15 ERA) was nearly as good as Matsuzaka, baffling the Sox to the tune of three hits and a run over seven innings.
"Their guy reminded me of [Jonathan Papelbon]," said Francona. "The life through the zone with the fastball. He's good. Don't look at that record. He's a good pitcher."
Matsuzaka, meanwhile, had a situation on his hands in the sixth. Randy Winn led off with a walk. Ray Durham followed with a single. Now it was Bonds at the plate with runners on first and second and nobody out.
Ultimately, Matsuzaka got him on a grounder to over-shifted shortstop Alex Cora, who fielded the ball well on the second base side of the grass before making the out at first.
"Well, that was definitely the biggest jam that I faced during the game in a situation where I couldn't avoid having to challenge him," said Matsuzaka, "At the same time, I felt that I wanted to challenge him, but overall I was just careful not to make any [mistakes] that he could get solid contact on."
Even after the out to Bonds, it was still runners at second and third and just one out. Bengie Molina hit a hard liner to short that was caught in the air by Cora. But Matsuzaka hit Nate Schierholtz on the arm with a 2-2 pitch to load the bases. Matsuzaka eased the tension in the park by striking out Rich Aurilia looking on an 89-mph cutter that was right on the black of the outside corner.
"I love it," Matsuzaka said.
Still, things got stressful after Matsuzaka's exit. On came left-hander Hideki Okajima in the eighth, and he started out by surrendering a leadoff walk to Winn and a single to left by Durham. It was déjà vu as Bonds again came to the dish, runners at first and second and nobody out. Okajima started out 2-0.
Then, pitching coach John Farrell came out for a message.
Farrell asked Okajima how he was doing. And before Farrell left the mound, he issued one message to his lefty.
In came a curveball for a strike. Then two fastballs, the latter of which was an inside offering that just caught the black.
"I knew Barry Bonds was waiting for an outside pitch, so Varitek wanted inside and the result was good," Okajima said through translator Jeff Yamaguchi.
Papelbon offered no such drama in the ninth, mowing the Giants down for a 1-2-3 frame that earned the righty save No. 16.
This was the first time Higashio got to watch his former prodigy up close on Major League soil, but he's been monitoring from afar.
"In the big leagues, you have to be really good with control, command and also velocity. Everything must be well-balanced to be a great pitcher," said Higashio, who won 251 games as a pitcher in Japan before managing Seibu.
"But soon, Matsuzaka will be a pitcher that a manager can definitely count on," continued Higashio. "And a pitcher who can definitely formulate a game and construct a game on his own, with the trust in him from the manager."
Not that Francona is lacking trust in Matsuzaka.
"Daisuke was really good, and on a day when he had to be every bit that good," Francona said.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.