BOSTON — The last-place Boston Red Sox traded pitching for power Thursday. Now they can use some name tags to stick on the jerseys of the newcomers.

Nine months after winning the World Series, the Red Sox unloaded five key members of that championship team, bringing to seven the number shipped out in a five-day span.

Jon Lester, John Lackey, Jonny Gomes, Andrew Miller and Stephen Drew. All gone.

Yoenis Cespedes, Allen Craig and Joe Kelly. Welcome to Boston.

“It speaks to where we are as a team,” Red Sox General Manager Ben Cherington said. “There’s nothing sort of celebratory about this. These moves are made because collectively as an organization, we haven’t performed well enough, in this year anyway.”

The Red Sox were 13 games out of the AL East lead when the day began.

A day off for the players was an around-the-clock marathon for team officials as they considered numerous possibilities before the trade deadline.

They parted with their two best starters, sending the left-handed Lester to the Oakland Athletics and right-handed Lackey to the St. Louis Cardinals. Then they weakened their bullpen by trading left-hander Miller to the Baltimore Orioles for Double-A left-hander Eduardo Rodriguez one day after Miller struck out the side in his final inning with Boston.

They also dealt away two underachieving hitters – outfielder Gomes going with Lester to Oakland and shortstop Drew heading to the rival New York Yankees for third baseman Kelly Johnson.

The Red Sox did get two key offensive pieces, outfielders Cespedes from Oakland and Craig from St. Louis. They provide power at a position that has produced just 17 homers this season, matching Cespedes’ total for the season.

Right-hander Kelly also came from the Cardinals and will go immediately into the rotation. He is 2-2 with a 4.37 ERA and has spent most of the season on the disabled list.

“It didn’t make any sense to us to trade both Lester and Lackey unless we were getting at least one major league starting pitcher back, if not major league players, total, back,” Cherington said. “It just would have made the next several months even more difficult to build to what we want to be.”

He’s intent on building a contending team for 2015.

The trades give the Red Sox the last two months of the season to assess their promising young starters. Rubby De La Rosa, Brandon Duckworth and Allen Webster already are in Boston. Anthony Ranaudo will be promoted from Triple-A Pawtucket and make his major-league debut Friday night against the New York Yankees.

Lester, who can become a free agent after the season, has said he hasn’t ruled out returning to Boston.

“He’s an Oakland A now so I don’t think it’s right for me to talk about that,” Cherington said.

The Red Sox offered Lester a four-year, $70 million contract in spring training. His market value has risen with his 10-7 record and 2.52 ERA but he said he didn’t want to focus on negotiations during the season.

After being traded, Lester tweeted, “Thank y’all cant tell you how much your support means to me and my family. Excited to contribute to a very talented @Athletics team!”

Another tweet from designated hitter David Ortiz: “Wishing my man Jon Lester all the best”

Cherington said third baseman Will Middlebrooks will be promoted from his rehab at Pawtucket before Friday’s game and struggling rookie Xander Bogaerts, who moved to third when Boston signed Drew on May 22, will return to shortstop.

Right fielder Shane Victorino could go on the disabled list with a back problem and Cespedes will start in his place until he’s healthy, Cherington said.

The Red Sox also sent cash and minor league left-hander Cory Littrell to St. Louis.

Miller was in demand because of his 2.35 ERA and the fact he’s a lefty who makes relatively little money.

“We had more calls on Andrew Miller than any other player on our team,” Cherington said.

In their final trade of a busy day, the Red Sox sent Drew to the Yankees in the first trade between the rivals since 1997.

“If we weren’t in the position we’re in, which I take responsibility for,” Cherington said, “these trades don’t happen.”

Cespedes, 28, won the past two Home Run Derby titles. The Cuban left fielder is in the third season of a $36 million, four-year contract he signed before spring training 2012. He’s batting .256 with 17 homers and 67 RBI, 26 doubles and three triples.

His 17 homers is the exact number hit this season by the nine Red Sox players who spent time in the outfield.

Kelly has made four starts since being activated from the disabled list July 11. Craig is batting .237 with seven homers and 44 RBI.

Kelly is “not a finished product but really talented,” Cherington said, “someone our scouts have liked for a long time.”

Johnson is hitting .219 with six homers and 22 RBI in 77 games and is on the disabled list. Boston also sent cash to New York.

Rodriguez, 21, is 3-7 with a 4.79 ERA in 16 starts with Double-A Bowie this year.

“I’m not excited about losing Eduardo, but you’ve got to give up quality to get quality,” Orioles Manager Buck Showalter said. “It’s a tribute to our farm system that we could sign and develop someone that brought (Miller.)”

General Manager Dan Duquette said, “We hated to give up a young left-handed pitcher. We tried a lot of other combinations short of Eduardo Rodriguez, but in this case it was required to make the deal.”