Matsuzaka scattered six hits and registered 10 strikeouts while throwing 108 pitches in the Red Sox's 4-1 victory. He gave up one run and walked one.
Nerves? Perhaps. But only if they're made of steel.
"It was really such a normal day for me," said Matsuzaka. "It's a day I've been waiting for for a very long time, but even given that fact, it felt surprisingly normal."
In one impressive afternoon of pitching against the Royals, the Boston right-hander showed his ability to baffle hitters and, when the need arose, get out of jams.
Take, for example, the 95-mph heater -- Matsuzaka's fastest pitch of the day -- that got rookie Alex Gordon to end the sixth inning. In an inning that could have been much worse, Matsuzaka minimized the damage. He did so by freezing Gordon every bit as much as the brave fans who came out amid the mid-30s temperatures to witness the unveiling of this talented right-hander from Japan.
Designated hitter David Ortiz, Boston's slugging superstar, watched much of Matsuzaka's performance from the clubhouse television. At times, the slugger couldn't believe his eyes.
"He reminds me of Pedro [Martinez] when he's pitching," said Ortiz. "He has total control of the game when he's out there, you know what I mean? He's got great stuff. When you watch him on TV, it's like a Nintendo game. He throws pitches that normally pitchers don't throw for a strike. He's got pitches that just disappear when they get to the plate."
None of the trained observers seemed to think that Matsuzaka's performance Thursday was anything above his norm.
"My guess is after what I've seen in Spring Training and today, that's how he pitches," said Red Sox manager Terry Francona. "Some pitchers, especially young pitchers, every three or four outings, you'll see a gem. And the other outings they can't command it and they lose. I don't think you'll see that with this guy. I think that's the way he pitches."
The bar has been set, and Matsuzaka looks poised to vault right over it.
"Well, up to now, given all the expectations that have surrounded me, I felt happy about those expectations, at the same time feeling that perhaps they were a little bit extreme," Matsuzaka said. "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."
David DeJesus put the first true dent in Matsuzaka's armor, belting a solo homer to right to lead off that sixth. That cut the Boston lead to 2-1. Esteban German then followed with a single up the middle. But in one key sequence, Matsuzaka struck out Mark Teahen looking on a 3-2 pitch and Jason Varitek fired to second to nail German on a stolen base attempt. The caught stealing, a borderline call which probably could have gone the other way, came back to haunt the Royals even more when the next batter -- Emil Brown -- stepped up and pummeled a double to left.
But after that strikeout on Gordon, Matsuzaka was out of trouble, but not out of the game. With 96 pitches over six innings, Francona surmised that Matsuzaka had one more in him.
"After the sixth inning ended, [pitching coach] John Farrell came over to me and asked me, 'Can you throw another inning?' I said, 'Yes,' and I went out there and I threw," said Matsuzaka. "Being out there on the mound, I get a rough sense of my own pitch count. I went out there sort of knowing that the seventh inning would probably be my last."
The Red Sox gave Matsuzaka the slight amount of breathing room he needed, scoring one in the first on a Manny Ramirez RBI double and another in the fifth when Julio Lugo stole third and scored on a throwing error by Buck.
Though Matsuzaka had just a 2-1 lead when he walked off after the seventh, the Sox created some comfort for the bullpen by scoring two in the eighth. Jonathan Papelbon nailed down Matsuzaka's first win with a save in the ninth.
"Daisuke really threw the ball the way he needed to on a day it was hard to score, the way the conditions were," said Francona. "We got one early and we added on and he made it stand up. He was terrific."
As for the cold, that didn't bother Matsuzaka either.
"I pitched in similar conditions last year in Morioka in the cold weather," said Matsuzaka. "Luckily for me, both my mind and body were familiar with pitching in these conditions, so I feel I was able to pitch fairly normally."
Just like in his exhibition season debut, Matsuzaka gave up a hit to the first batter he faced. DeJesus did the honors, belting a single up the middle on Matsuzaka's third Major League pitch. But, aside from a walk to Teahen, there were no further complications in the inning. Matsuzaka got out of the two-on, one-out jam by inducing Brown into a 1-6-3 double play.
It was clear that Matsuzaka was getting into a groove. His first Major League strikeout was a 94-mph fastball past the bat of Ross Gload to end the second. Matsuzaka then punched out Buck looking to start the third.
The fourth inning was his most dominant, as Matsuzaka struck out the side on 14 pitches. He finished the frame with a flourish, blowing a high fastball by Brown.
However, a somewhat sticky situation developed in the fifth. Matsuzaka gave up a leadoff single to Gordon -- the first Major League hit for the prized rookie -- and a two-out single to Buck. That set up runners at the corners, representing the first time all day the Royals had a runner 90 feet from home plate. But that was as far as they would get, with Matsuzaka getting Tony Pena Jr. on a tapper back to the mound. It was the 24th pitch of the inning for Matsuzaka, who threw 78 over the first five innings.
"Major League hitters, after you go through the order once or twice, get a beat on you," Francona said. "He didn't let them. He started throwing different pitches in different counts. In the fifth inning, they hit a couple of balls hard. He came back in the sixth and seventh and was as good as he was early."
Varitek enjoyed the view from behind the plate a lot better than those Kansas City hitters did from the batter's box.
"We had a game plan, and he executed it," Varitek said. "The toughest thing for me is to adapt to his style, just try to figure out what it is. Thinking ahead is my job, because he doesn't get locked into a particular pitch depending on the count."
Matsuzaka might be a mystery to the hitters and even, at times, to his catcher. But there no longer seems to be a question of whether he will be a good pitcher at the Major League level. On the heels of Thursday, the more relevant question seems to be, "How good?"
There will be more evidence on display to answer that inquiry on Wednesday, when Matsuzaka makes his first Fenway start against the Mariners.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.