CHICAGO -- Gavin Floyd made sure the Boston Red Sox's season-best winning streak ended at six games.
The right-hander helped the Chicago White Sox prevent a four-game Boston sweep with a 4-1 win Sunday at U.S. Cellular Field.
After winning 10-3, 10-3 and 1-0 in the first three games of the series, the Red Sox were held hitless through the first six innings by Floyd (2-3), who was seeking the 18th no-hitter in White Sox history. Just eight days earlier, teammate Phil Humber threw a perfect game at Seattle.
"They were hitting against him, but he looked real good," Red Sox manager Bobby Valentine said of Floyd. "He established his fastball, and it looked like he had a dynamic curveball. He really held us at bay."
The win snapped a five-game losing streak for the White Sox, who climbed back to .500 (11-11), while the Red Sox fell one game below .500 (10-11).
Still, the Red Sox made a tremendous amount of progress on their seven-game road trip, sweeping a three-game series in Minnesota before taking the first three in Chicago.
"This week, it seemed like things came together nicely," Valentine said. "We're still a work in progress, I believe."
The Red Sox return to Fenway Park to begin a seven-day, six-game homestand against Oakland (Monday to Wednesday) and Baltimore (Friday to May 6).
"It's great to be going home," Valentine said. "These guys played their butt off. We've battled travel and weather. They're a tough group."
Floyd lost his no-hitter bid in the top of the seventh when Dustin Pedroia knocked a one-out single just past the grasp of diving second baseman Eduardo Escobar. Adrian Gonzalez struck out, and David Ortiz blasted a two-out double down the right field line, advancing Pedroia to third. Cody Ross singled, driving in Pedroia and moving Ortiz to third.
The White Sox countered with reliever Addison Reed to pitch to Nick Punto, who grounded out to first baseman Adam Dunn to end the inning and minimize the damage, leaving the White Sox ahead 3-1.
Floyd pitched 6 2/3 innings, allowing one run on three hits. He walked one and struck out nine. Of his 111 pitches, 70 were strikes.
Red Sox ace Josh Beckett (2-3) suffered the loss, allowing the first three Chicago runs on six hits. He walked three and struck out eight. Beckett tied a career high for pitches thrown in a game (126), of which 85 were strikes.
"He had good movement and location," Valentine said of Beckett. "It was just one of those days where we didn't score for him."
White Sox lefty Matt Thornton pitched the final 1 1/3 innings to earn his first save of the season.
The White Sox scored three runs in the bottom of the first inning, which would prove to be all the offense they'd need.
Alejandro De Aza singled to lead off the game, moved to second on Brent Lillibridge's sacrifice bunt and scored on Alex Rios' single. Adam Dunn then stroked a two-run homer to right field to make it 3-0.
"It was a pretty tough hole to put the team in, especially with a guy that's pitched the way he has against us in the past," Beckett said of both his first inning failures and Floyd's overall record vs. Boston, now 7-0 lifetime.
"I struggled to finish my curveball," Beckett said of the first-inning problems. "That two-run homer was the difference in the game. As a pitcher, you try to minimize damage. You try to just give up one run and move on.
"Still, it was a pretty good road trip as a team, anytime you can sweep one series and take three in a four-game series."
Boston managed just one baserunner in the first five innings, that coming in the fifth when Ross worked Floyd for a two-out walk. However, Punto struck out to end any semblance of a threat.
NOTES: Boston third baseman Kevin Youkilis was a late scratch just before game time with tightness in his lower left back. He was replaced in the starting lineup by Punto. "He should be OK for tomorrow," Valentine said of Youkilis. ... Boston's 1-0 win over Chicago on Saturday was the first time the Red Sox have beaten the White Sox by that score since 1993. According to the Elias Sports Bureau, winning Red Sox starter Jon Lester became the first Boston pitcher to start and win a 1-0 game in Chicago since Jim Lonborg at old Comiskey Park in 1969. ... Gonzalez knocked in the only run in Saturday's game, the 657th RBI of his career, but his first in a 1-0 game. ... Boston failed to earn the second road-trip sweep of at least seven games in team history. The Red Sox had a 9-0 road-trip sweep of California (three games), Seattle (two games) and Oakland (four games) in 1977. ... Including Sunday's loss, the Red Sox are now 7-6 on the road and 3-5 at home.