BOSTON – David Ortiz hit a two-run homer, four Boston pitchers combined on a three-hitter, and the Boston Red Sox beat the Oakland Athletics 4-0 on Saturday to complete a sweep of a rain-delayed, day-night doubleheader.

In the opener, Jason Varitek hit a two-run homer, Jon Lester allowed three hits in six innings, and the Red Sox won, 9-3. That game was delayed twice, for 45 minutes after the sixth inning and for 2 hours, 15 minutes after the seventh.

There was a one-hour delay in the top of the fifth in the nightcap. The first game had been moved up to noon from 1:10 p.m. to make room for the second game that was rescheduled from today to avoid Hurricane Irene’s effects.

Erik Bedard allowed two singles in four innings in Game 2 before being replaced by Alfredo Aceves (9-1) when play resumed. Aceves pitched three hitless innings and Daniel Bard allowed a single in the eighth before Jonathan Papelbon pitched a perfect ninth.

Ortiz went 5 for 8, driving in four runs and scoring three in the doubleheader.

The Red Sox, 8-3 in their last 11 games, increased their American League East lead to two games over the New York Yankees, who had a doubleheader at Baltimore rained out.

Fans with tickets for the scheduled 5:05 p.m. start were allowed through the turnstiles during the second delay in the opener. The game ended at 6:08 p.m.

At night, the Red Sox took a 2-0 lead in the second against Graham Godfrey (1-2) when Dustin Pedroia doubled and Ortiz hit his 27th homer. They made it 3-0 in the fourth on consecutive singles by Pedroia, Ortiz and Jed Lowrie and an RBI groundout by Jarrod Saltalamacchia.

They scored their final run in the sixth off Josh Outman. With one out, Lowrie reached second on a two-base throwing error by third baseman Scott Sizemore. After Carl Crawford flied out, Saltalamacchia hit a pop fly to short right field. First baseman Brandon Allen ran back but, as he looked up into the rain, the ball bounced off his glove and he fell. Saltalamacchia was credited with an RBI double.

Bedard walked just five batters in his other four games with Boston but walked four of the first seven Oakland hitters. His last batter, Anthony Recker, singled for his first major league hit before play was halted in the fifth.

In the opener, Lester (14-6) allowed two runs, one of them earned, walked two and fanned four, improving to 7-0 with a 1.54 ERA in nine afternoon starts.

Lester started under bright skies, but heavy rain fell on and off during the middle innings before play was halted as he prepared to take the mound in the seventh.

“The conditions were really bad. The mound wasn’t bad, but anytime you took the ball out of your glove it was wet,” he said. “I had no grip.

“I was trying to tell the umpires that. Maybe the second time it went to the backstop made them realize it wasn’t safe.”

Ortiz added a pair of doubles and drove in two runs, and Mike Aviles had three singles for Boston.

Allen hit a solo homer for Athletics.

The second delay of the opener came after Varitek bounced weakly to the mound, ending the seventh.

Crew chief Tim McClelland told a reporter between games that the first game had to end before the second could be started. He said there was no way to call it early and then finish the doubleheader.

“Yes. That’s what Joe (Torre) told me,” McClelland said.

Torre is the executive vice president of baseball operations.

“Actually, there were no options. We were just waiting to get started again,” Oakland Manager Bob Melvin said.

“Both teams have to deal with it. It’s not ideal but both teams have to deal with it. So you just play.”

Boston Manager Terry Francona said the umpires consulted with MLB officials regarding the decision to finish the first game before starting the second.

“To play the second game, we’ve got to play the first one,” he said. “We’ve done it the other way a couple of years ago against Minnesota.”

In April 2009, Boston led 10-1 against the Twins when the game was halted by rain after seven innings so the teams could get ready for the second game.

“That was an aberration,” McClelland said. “I talked to (Torre). According to the rules, that can’t happen or shouldn’t happen.”