BOSTON _ The Red Sox and Yankees completed their regular-season series last night at Fenway Park, but don’t be surprised if the two clubs meet again this year.

It’s almost inevitable that scenario will play out in the playoffs, but before each team can even think about the postseason, Boston and New York were concentrating on the task at hand.

The pitching matchup of Roger Clemens and Curt Schilling didn’t disappoint, but it was one mistake by the Red Sox starter that allowed the Yankees’ Derek Jeter to hit a three-run homer in the top of the eighth en route to a 4-3 victory.

Boston threatened with two outs in the bottom of the ninth inning with the bases loaded and slugger David Ortiz at the plate. But, New York closer Mariano Rivera did was he does best and got Ortiz to pop out to short to end the game.

“The way Clemens and Schilling pitched tonight,” said Red Sox third baseman Mike Lowell, “the fans got their monies worth right up until the last pitch.”

New York took 2 of 3 games from Boston over the weekend and the Red Sox lead in the A.L. East stands at 4 ½ games with 12 games remaining on their schedule.

“Tonight boiled down to two mistakes,” Schilling said of the home runs he allowed to Jeter and Robinson Cano (in the fifth inning). “I missed horribly in probably the most crucial situation of the game, that’s all it was. . . I was trying to bounce that ball (to Jeter) in the dirt. I don’t ever try to take credit away from a hitter, but I was trying to bounce that ball.”

Last night was a rematch from Game 7 of the 2001 World Series when Schilling played for Arizona and Clemens for New York. The excitement wasn’t lost on anyone last night. Schilling worked 7 2/3 innings and allowed four runs on six hits with no walks and two strikeouts.

“Phenomenal,” said Red Sox catcher Jason Varitek on Schilling performance. “He did a great job.”

Clemens lasted six innings and surrendered one unearned run on two hits with three walks and four strikeouts.

“He certainly hasn’t forgotten how to pitch or compete,” said Red Sox manager Terry Francona.

Now that this series is in the books, both teams can concentrate on the final two weeks of the season. Boston is trying to win a divisional title for the first time in more than a decade, and New York is battling for the wild card.

“I would rather be 4 ½ up than 4 ½ down,” said Schilling. “We really don’t think much about that. We’re very good at staying focused on the game at hand.”

Boston left after last night’s game for a seven-day, six-game road trip through Toronto and Tampa before returning home to host Oakland and Minnesota. New York hosts Baltimore and Toronto and closes out the season on the road in Tampa and Baltimore.

There’s still plenty of baseball to be played.

“Absolutely,” said Red Sox left fielder J.D. Drew. “We still have to play quality-winning baseball and go from there.”

Even though the Red Sox lost the regular-season final series to New York, Boston’s clubhouse was a bit jovial after the game. It’s a good sign that the players are relaxed.

“It would have been nice to win tonight,” said Red Sox utility man Eric Hinske. “We have a 4 ½ game lead heading into a road trip and hopefully have a good series against Toronto and Tampa. We’re in a good spot. No one is panicking. We’re just going to try to finish strong, make the playoffs and take it into the postseason.”

Ortiz, who had an opportunity to make magic happen again last night in his ninth-inning at-bat before Rivera won the battle, feels good about the club’s mindset in the final stretch of the season. “We have to keep playing the way we have been,” he said. “Nobody is feeling pressure around here. We just lost one game and we move forward and try to win the series in Toronto.”

That attitude has worked for the Red Sox in the past and they’re not about to deviate from that plan. There’s too much at stake for that to change.

“We’ve played hard all year and we’ve been winning this division all year long,” said Red Sox second baseman Dustin Pedroia. “We’ve got 12 more games left and we have to make a push.”

And, Boston will add a huge bat to the lineup once Manny Ramirez (strained oblique) returns, which could be as early as tonight or tomorrow against the Blue Jays.

“He’s looked good in BP,” said Lowell. “Putting him back in the lineup is not like a September call-up.”

As the Red Sox players left the clubhouse last night, the message was the same: “We didn’t quit and that’s huge,” said Varitek. “If we keep playing like this we’ll be okay.”

jmcdonal@projo.com