BOSTON's DAISUKE MATSUZAKA throws to Kansas City's Tony Pena Jr. Matsuzaka threw seven strong innings Thursday in a 4-1 victory at Kauffman Stadium.

Kansas City, Mo. ? After striking out three times, Ryan Shealy sounded amazed.

“I didn’t know he threw that hard,” he said.

Dice-K was more than OK in his major league debut.

With millions of early rising viewers keeping track on Japanese television, Daisuke Matsuzaka struck out 10 in seven innings in his major league debut Thursday to lead the Boston Red Sox over the Kansas City Royals 4-1.

“I can’t say that my overall condition was that great today, but I think the role of a starting pitcher is to set up the game and give my teammates the opportunity to win,” he said through an interpreter. “I feel like I was able to do that today, so I was satisfied.”

On a cold, blustery afternoon, Matsuzaka (1-0) allowed six hits, including a sixth-inning homer by David DeJesus, and walked one. He looked every bit the ace Boston committed $103 million to.

“Any time you have that good of a fastball and the offspeed to go with it, it’s tough,” Shealy said. “He mixes up speed on his pitches and moves it in and out. You can’t really get comfortable with him.”

His fastball clocked at 95 mph and his famed array of fastballs, changeups and breaking pitches at times was dazzling. Flashing a reddish-orange glove during his slow-motion windup, he retired 10 batters in a row during one stretch starting with the final out of the first inning. He struck out the side in the fourth on 14 pitches.

Red Sox executives have business cards printed in English on one side and Japanese on the other. Restaurants in the Fenway Park area are beginning to offer Japanese dishes and more than 100 Japanese media have been chronicling his every step. About 200 media were on hand to chronicle his every move.

“Up to now, given all the expectations that have surrounded me, I’ve felt happy about those expectations,” he said. “But at the same time feeling like perhaps they were a little bit extreme. But speaking for myself and for all the fans that have supported me here, it’s great that I was able to come out here and record a victory in my first start.”

In addition to his pitching, Matsuzaka proved himself a skillful fielder, pouncing off the mound three times to field weak grounders.

“He’s got a bunch of plus-pitches,” Shealy said. “A lot of guys have a good fastball or have good offspeed stuff, but he seems to have both.”

Kansas City manager Buddy Bell strained to think of a pitcher to compare him with.

“I will tell you this – I was pretty impressed,” Bell said. “He just really had a feel for what he was doing. Everything he did was absolutely solid. Everything that he tried to do.”

Matsuzaka left the Seibu Lions to sign a $52 million, six-year contract with the Red Sox, who bid $51,111,111 for his rights.

The crowd of 23,170, bundled on a 36-degree day, booed Matsuzaka in the first when he stepped behind the mound and started doing half jumping-jacks, snapping his heals together in the air.

He gave up a single to DeJesus on his third pitch. He walked Mark Teahen with one out, then got Emil Brown to ground into a double play, but then didn’t allow another runner until Alex Gordon singled leading off the fifth.

DeJesus homered on Matsuzaka’s second pitch of the sixth. Estaben German followed with a single, and Matsuzaka’s shoulders seemed to droop, and pitching coach John Farrell visited the mound. German was caught stealing as Teahen took a called third strike, Brown doubled off the left-field wall, but Gordon took a called third strike, the first of three straight strikeouts.

“Major league hitters, after you go through the order once or twice, get a bead on you, and he didn’t let them,” Boston manager Terry Francona said. He started throwing different pitches on different counts. He came back in the sixth and seventh and was good as he was early.”

DeJesus joked about the famed “gyroball,” a pitch Dice-K may or may not throw.

“I think it was the gyroball,” he laughed when asked what he hit for the home run. “No, it was a fastball. I didn’t think it was going to go, but the ball kept carrying.”

Matsuzaka, who wasn’t satisfied with his spring-training performances, threw 74 of 108 pitches for strikes. The 26-year-old right-hander, 108-60 with a 2.95 ERA and 1,355 strikeouts for Seibu, did not have to face two of Kansas City’s top hitters: Mike Sweeney and Mark Grudzielanek were given the day off following a night game.

J.C. Romero and Jonathan Papelbon finished, with Papelbon striking out two of three batters for his first save.

Zack Greinke (0-1), who missed almost all of last season due to social anxiety disorder, struck out seven in seven innings, allowing two runs and eight hits.

Manny Ramirez had an RBI double in the first, and Julio Lugo doubled in the fifth, stole third and scored on catcher John Buck’s throwing error.

Boston added two runs in the eighth on Joel Peralta’s wild pitch with a runner on third and Coco Crisp’s RBI single, his first hit in 10 at-bats this season.

Notes: Gordon, the Royals’ top prospect, had been 0-for-8 until he singled leading off the fifth. He also let a grounder get under his glove at third for an error. … The media contingent was the biggest the Royals saw at home since the seventh game of the 1985 World Series.