The Boston Red Sox are rumored to have made a deal for Jon Lester. The rumor mill has the Sox trading their left-handed ace to the Oakland Athletics along with slugger Jonny Gomes for A’s outfielder Yoenis Cespedes.

A WEEI.com beat writer Alex Speier has confirmed via Twitter that the deal is in place, although it hasn’t been officially announced by either side.

The deal is a shocker that will completely shift the dynamic of the American League. Cespedes is having a huge season for the A’s, batting .256 with 17 home runs and 67 RBI and a .767 on-base plus slugging. He had been arguably Oakland’s top hitter, but the addition of Lester gives the A’s perhaps the deepest rotation in baseball.

Lester will join youngster Sonny Gray, Scott Kazmir and fellow trade acquisition Jeff Samardzija, who was acquired from the Chicago Cubs earlier this season.

That rotation figures to be a difficult one to overcome in a playoff series, and the A's have made masterful use of platoons in recent years to wallpaper their lack of offensive stars, but Cespedes is one of their better defenders in addition to being a potent bat. His arm has become one of the must-see attractions in baseball, but now that'll be on display in Beantown.