BOSTON – Carl Crawford was hoarse Saturday when he spoke at his Boston Red Sox introduction.

Otherwise he’s pretty much perfect for them.

“I don’t know where that came about,” the speedy Crawford said, his words slow and scratchy. “I can’t believe it happened at this moment.”

And what a moment it was for Boston as the four-time All-Star buttoned up his white Red Sox jersey with his familiar No. 13 on the back at the official announcement that he had signed a seven-year deal as part of what may be baseball’s best lineup.

“He’s one of the most dynamic players in the game,” Manager Terry Francona said. “He can change the game all the time — on defense, on the bases, at the plate — and not a lot of players can do that. He’s a really special player.”

This year, Crawford won his first Gold Glove, stole 47 bases and posted career highs of 19 homers and 90 RBI. He hit .307, the fifth time in six seasons he was over .300. He also led the AL with 13 triples. He’s led the league in stolen bases four times in his nine seasons, all with Tampa Bay.

Now add that to slugging first baseman Adrian Gonzalez, traded from the San Diego Padres a week earlier, Kevin Youkilis, Dustin Pedroia and David Ortiz, and opposing pitchers may not enjoy taking the Fenway Park mound with the short right-field foul pole and the high Green Monster in left.

“Before the season even starts you tell in your mind, ‘World Series, postseason, all that stuff’ with Boston,” the 29-year-old Crawford said.

“You know it actually might happen.”

Crawford reached a preliminary agreement Wednesday night on a $142 million contract after becoming a free agent. Gonzalez, 28 and entering the last year of his contract, is expected to sign a seven-year extension in 2011.

Pedroia is signed through 2014 with a club option for 2015, Youkilis’ deal runs through 2012 with a club option for 2013, and center fielder Jacoby Ellsbury can’t become a free agent until after the 2013 season.

That’s five key players the Red Sox could keep for three more years.

“It’s a pretty rare opportunity,” General Manager Theo Epstein said, “for an organization to add two of the best players in the game, in my opinion, under 30 to a core that I feel is already young and in its prime.”

Beset by long-term injuries to Pedroia, Youkilis and Ellsbury, Boston finished third in the AL East behind the Rays and New York Yankees. The Red Sox also got subpar seasons from starters Josh Beckett and John Lackey.

Comebacks from that group would enhance prospects for winning the division and returning to the playoffs after last season’s absence.

Ellsbury, with a total of 120 stolen bases in 2008 and 2009, was limited to 18 games last season because of rib injuries. Almost fully recovered, he and Crawford, called by Epstein “a game changer,” could provide a speedy 1-2 punch at the top of the order. Crawford said he doesn’t mind where he hits in the lineup, and Francona indicated it would be second or third.

“Our best team is when Jacoby’s hitting first,” Francona said.

The Crawford-Ellsbury combination could be just as impressive on defense.

“I know there’s a bunch of historical names and I just want to be part of that” group of Red Sox left fielders — Ted Williams, Carl Yastrzemski, Jim Rice, Manny Ramirez, Crawford said. “Hopefully I can go down as one of the best left fielders that played here.”

Epstein and Francona met Nov. 30 with Crawford and his agents, Greg Genske and Brian Peters, in Houston, Crawford’s hometown.

“We felt like we had made a connection with Carl at the meeting and that he was really intrigued by being part of our lineup, especially after we traded for Adrian,” Epstein said.

The Los Angeles Angels were the other serious bidder, but Crawford said he preferred to stay in the AL East.

“I have a 6-year-old son. I think he was a closet Boston fan,” Crawford said. “When I told him I was coming to Boston he was more excited than me. And that’s when I knew I had made the right decision.”

Overshadowed by the signing of Crawford was the return of catcher Jason Varitek, 38, to the team for a 14th season on a $2 million plus incentives, one-year deal announced Friday. He’s expected to share playing time with and be a mentor to 25-year-old Jerrod Saltalamacchia.

DODGERS: Los Angeles signed outfielder Tony Gwynn Jr. to a one-year contract worth $675,000.

Gwynn played last season for San Diego, the former team of his Hall of Fame father, Tony Gwynn. Gwynn Jr. became a free agent when San Diego failed to offer him a contract for 2011.

Gwynn, who is one of baseball’s top defensive outfielders, has a .276 career batting average as a pinch hitter.