The Boston Red Sox are waiting for Jon Lester — and they are not.

General manager Ben Cherington said the team is pursuing other free agents — and trade opportunities — to fill out its rotation.

“We need to build a rotation and we need to be in on all sorts of stuff, and we have been in all sorts of stuff,” Cherington said Tuesday. “There’s probably 15 to 20 starting pitching scenarios we’ve talked about and worked on. … We’re going to build a good rotation.”

Cherington acknowledged Boston has spoken with former pitcher Justin Masterson, who came up through the Red Sox farm system before being traded in 2009 during his second big league season. The right-hander went 7-9 with a 5.88 ERA for Cleveland and St. Louis this year, when he spent time on the disabled list because of a knee injury.

After finishing last in the AL East at 71-91, the Red Sox revamped their lineup by adding free agents Hanley Ramirez and Pablo Sandoval. They are now focusing on filling two rotation spots.

Lester is their clear first choice. The left-hander has pitched nearly all his nine-year career with Boston, winning two World Series championships with the Red Sox. But he was traded to the A’s this summer.

Whether Boston ends up signing Lester or not, Cherington thinks results are what matters most.

“I think our fans expect us to deliver on the field and win games,” he said. “In order for us to give the best chance, we have to add to the pitching staff. There are all sorts of ways to do that. Of course there’s a connection to certain players more than others. But ultimately they care about the people we put on the field.”

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