BOSTON -- The Red Sox already knew that Justin Masterson could thrive as a starter, long reliever or a setup man. Now they know that mornings aren't a problem either for the swingman who just seems to get outs whenever he pitches.

Like everyone else at Fenway Park on Monday, Masterson was an early-riser, drawing the 11:05 a.m. ET start in the annual Patriots Day contest. The righty stepped right into the starting rotation in just the seamless way the Red Sox expected him to, paving the way for an 12-1 victory that completed a four-game sweep of the Orioles.

Filling in for the disabled Daisuke Matsuzaka (right shoulder strain), Masterson fired 5 1/3 innings, giving up four hits and a run. He walked two and struck out three, throwing 84 pitches.

To Masterson, the early-bird special consisted of a steady diet of quality pitches, and even a fastball that hit as high as 96 mph on the radar gun.

"I didn't even notice [the early start time]," Masterson said. "I couldn't have even told you what time it was. For me, it was time to start. The body was ready to go."

Though Masterson was stretched out as a starter during Spring Training, it was his first official turn in the rotation since July 4 of last season.

There aren't many pitchers who can go from one role to another as easily -- not to mention effectively -- as Masterson, something the Red Sox try not to take for granted.

"Today was a real good example," said Red Sox manager Terry Francona. "It's probably not fair to expect that. He was sharp from the very beginning. He maintained the velocity on his fastball, the life on his fastball, the depth on his breaking ball. Eleven o'clock in the morning start ... there are a lot of things that he just went out and did. We're very fortunate -- we know that."

While Masterson was the stand-out performer from the mound, there were numerous big performances from the offense. The headliner was Dustin Pedroia, who banged out four hits, scored three runs and drove in three, looking a lot like the player who won the American League Most Valuable Player Award last year.

"We swung the bats really well the whole series," said Pedroia. "It was huge for us. Some guys struggled the first couple of games, but through the course of the year, you find that rhythm. You just have to have good at-bats and continue to see the ball. That's the big thing."

David Ortiz's revival was another key on the offensive side. The big slugger, who came into the day hitting .170, belted a double and a triple and drove in two runs.

"When I go to hit, I don't think about anything but me getting it done at the time," said Ortiz. "I know people expect me to get it done. I've gotten it done before and I'm going to keep getting it done."

From the leadoff spot, Jacoby Ellsbury had three hits and scored three runs. Jason Varitek added two hits and two RBIs, including a solo homer over the Green Monster.

In possession of a mere 3-1 lead after five innings, the Red Sox broke it open with three in the sixth and six in the seventh.

At this time last week, all the talk was about Boston's slumping offense.

"That's why you don't panic the first two weeks of the season," Francona said. "You look up at one point and Jacoby's hitting .275 and [Pedroia] the same thing. We say it every year, but it happens. Everything gets blown out of proportion and you just try to play good baseball, because at some point in the season, when you start logging enough at-bats or innings and you get it into the grind of the season -- if you're good, it shows."

As for Masterson, the 24-year-old continues to shine.

Where did his extra heat come from on Monday?

"I wanted to keep the intensity I had coming in from the bullpen, when it seemed my velocity kind of elevated," Masterson said. "I really just wanted to keep that intensity coming into my start. I was really happy that I was able to do that today."

After scratching out just two runs in Sunday's win, the Red Sox went to work early in this one against towering Orioles left-hander Mark Hendrickson.

Ellsbury led off the first with a pop fly double down the left-field line that shortstop Cesar Izturis just missed making a play on. Pedroia followed with a single up the middle for the first run of the game. Ortiz lifted an opposite-field double off the Green Monster to put runners at second and third with nobody out. Pedroia wound up scoring on Rocco Baldelli's fielder's-choice grounder.

The Red Sox scored in much less methodical fashion in the second, as Varitek led off with his third homer of the season.

Aside from the third inning, when the Orioles chipped away with two infield hits and a sacrifice bunt for a run, Masterson cruised. Pedroia (RBI single) and Ortiz (two-run triple) padded the lead in a three-run bottom of the sixth. From there, it was all Red Sox.