BALTIMORE -- Tim Wakefield got his knuckleball to flutter at just the right time against the overeager Baltimore Orioles, who flailed away with little success when it mattered most.

Wakefield pitched six perilous innings without allowing an earned run, leading the Boston Red Sox to a 4-1 victory Sunday and a three-game sweep.

Adam Stern drove in two runs for the Red Sox, whose 5-1 start is their best since 1999. Boston outscored Baltimore 20-10 in the series and has won eight straight against the Orioles dating to September.

For the Red Sox, the best part about their good start is that it occurred on the road. Boston plays its home opener Tuesday against Toronto.

"I think Fenway will be jumping. It's a great way to go home," Boston manager Terry Francona said.

Wakefield (1-1) retired the side in order only once. The right-hander twice worked out of bases-loaded jams and stranded 10 runners before leaving with a 4-1 lead.

"He's tough when he's got that thing moving, so as an offense you have to start trying to get base hits and not overswing," Orioles manager Sam Perlozzo said. "Sometimes we get a little too anxious. We needed to take what he gives us."

Wakefield gave the Orioles plenty, but not when it counted. Despite allowing five hits, two walks and hitting two batters, he lowered his ERA from 17.18 to 6.52 following a horrible season debut.

"You always want to get back out there. I had pretty good stuff in Texas, almost too good," Wakefield said. "I couldn't control it and I couldn't throw it for strikes. When that happens, you start walking guys and it leads to really big innings. Today I felt more comfortable."

And that made the Orioles very uncomfortable. Baltimore went 2-for-13 with runners in scoring position, including 2-for-10 against Wakefield.

"I played with him for three years and faced him a lot," Orioles first baseman Kevin Millar said. "It's a 50-50 thing when you're facing a knuckleballer. You just have to keep battling and take your hacks."

Mike Timlin worked the seventh, Keith Foulke pitched a perfect eighth and Jonathan Papelbon got three outs for his third save, the second in two days. With runners at the corners and one out in the ninth, Jay Gibbons and Millar fouled out.

Ramon Hernandez had three hits for the Orioles, who left 14 runners on base. Baltimore has lost four straight after starting 2-0.

"You're always worried when your team doesn't hit well and doesn't pitch well," Perlozzo said. "We need to start clicking a little bit better in all areas."

Boston went up 4-1 in the sixth, scoring two runs with two outs after Orioles starter Rodrigo Lopez walked the bases loaded. Stern got an RBI single on a grounder that handcuffed Millar at first, and Mark Loretta chased Lopez (1-1) with a single before John Halama retired David Ortiz on a grounder to first.

In the bottom half, a double by Hernandez and a single by Chris Gomez put runners at the corners with no outs. Wakefield then capped his gritty performance by striking out Corey Patterson, David Newhan and Luis Matos.

"You just try to minimize the damage and you get your concentration down to one hitter at a time, in and out," Wakefield said. "I was fortunate enough to get three strikeouts there and get us out of the inning."

Wakefield threw 93 pitches, 63 for strikes.

The Orioles got an unearned run in the first inning. After Newhan's grounder to second base went through Loretta's legs, Newhan stole second and scored on a single by Miguel Tejada.

"Early on, we made it hard on (Wakefield)," Francona said. "He made some real good pitches, stranded some runners, gave himself a chance to settle down."

Baltimore loaded the bases with two outs in the fourth before Wakefield got Matos to hit into a fielder's choice.

Boston then took a 2-1 lead in the fifth. Two singles and a sacrifice bunt preceded an RBI single by Stern, and a throwing error by second baseman Gomez enabled another run to score. It was the first error by a Red Sox opponent this season.

Notes

• The Red Sox made two errors, twice as many as they had in their first five games.
• Since 1999, Boston is 44-18 at Camden Yards.
• Hernandez is batting .688 and has reached base in 14 of 20 plate appearances.