Red Sox second baseman Dustin Pedroia and manager Terry Francona congratulate Jon Lester on a job well done last night.

The Providence Journal / Bob Breidenbach

DENVER — It was a lifetime between championships the last time the Red Sox won the World Series.

This time, it was only four years.

But that’s a long time if you’re 23-year-old Jon Lester, who, a year ago at this time, had no guarantees that he’d live to be 27. Or even 24.

Called up from Pawtucket in June of 2006, he was cruising along with a 7-2 record in August when he was diagnosed with a form of anaplastic large cell lymphoma.

Confronted with the big C, suddenly W’s and L’s paled in importance.

One day, the young lefty appeared to have a long and successful career ahead of him. The next, he didn’t know if he’d ever pitch in the major leagues again.

So how wonderful was it that, in this most special of Red Sox seasons, Lester was not only the starting pitcher, but also the winning pitcher, as Boston swept the Colorado Rockies with a 4-3 victory last night at Coors Field?

His was the best of some fabulous stories last night as the Sox, who went 86 years without a championship before winning in 2004, won the World Series for the second time in four years.

Before the game, he had said: “Hopefully, I can be effective and give my team a chance to win. That’s all I’m looking at doing — get into the sixth or seventh inning and turn it over to our bullpen, which has been phenomenal this year.”

Lester was phenomenal last night, holding the Rockies scoreless into the sixth inning, giving up just three hits.

“I’m so proud of the way Jon Lester pitched,” Red Sox manager Terry Francona said. “I think it was very appropriate that he got the win.”

“I’m ecstatic for Jon,” said Mike Lowell, who was named the Series MVP. “We all know the story of what he’s had to overcome. He’s a great person with a bright future.”

And what of Lowell’s future?

He’s a free agent now, having just made one of the greatest contract pitches in the history of baseball.

How can the Sox not sign him to a lucrative new deal after he capped what has been a dazzling performance in this World Series by going 2-for-4 last night, hitting a leadoff double in the fifth and scoring on a single by Jason Varitek, then starting off the seventh with a home run?

Indeed, in the post-game celebration, when thousands of Boston fans turned Coors Field into Fenway Park West, they began to chant “Re-sign Lowell! Re-sign Lowell!” before launching into yet another chorus of “Let’s Go, Red Sox!”

Speaking of homers, how big was the blast by Bobby Kielty, pinch-hitting for reliever Mike Timlin in the top of the eighth?

Signed by the Sox in August after he had been released by the Oakland A’s, Kielty’s blast proved to the winning run.

Certainly, this big win wouldn’t have been possible without Big Papi, who delivered again last night, driving in Boston’s first run with a sharp single in the first that brought home spectacular rookie Jacoby Ellsbury, who had opened the game with an opposite-field double down the line in left.

Ellsbury had an incredible Series, finishing with 7 hits in 16 at-bats — a .438 batting average. And if you think Manny would have flagged down that gut-wrenching liner to deep left hit by Jamey Carroll with one out in the bottom of the ninth, well, you must think Joe Torre is going to invite George Steinbrenner to his Christmas party this year.

Ellsbury’s speed on the base paths, and in the outfield, thrills, giving the Red Sox a dimension they have so often lacked.

He wasn’t the only rookie to play like a seasoned veteran in this World Series.

Dustin Pedroia did it, not only against the Rockies, but throughout the season, making a convincing case that he deserves to be Rookie of the Year in the American League.

He hit .317 this season, then led off Game One of the World Series at Fenway with a home run, following up on his heroics in the seventh game of the ALCS, when he homered to clinch the decisive win over the Indians, capping a Boston comeback from a 3-1 deficit in the series.

And we’ve yet to mention Josh Beckett, who after winning 20 games (and, most likely, the Cy Young Award) during the regular season, was unbeatable in the postseason, winning four games, including an overpowering performance in Game One in Boston.

Give a tip of your Sox cap, too, to catcher and captain Jason Varitek. And to first baseman Kevin Youkilis, who put his team ahead of his ego throughout the season, but especially the last two games in Colorado when, in order to keep Ortiz’s bat in the lineup, he had to sit the bench, even though he’d been pounding the ball in the postseason.

It’s appropriate to close with Jonathan Papelbon. That is, after all his role — one he filled brilliantly, coming out of the bullpen to put the finishing touches on the final three games of the Series.

When he threw a third strike past pinch-hitter Seth Smith for the final out last night, he threw his glove sky-high.

Four years ago, when the Red Sox were beating St. Louis, he was pitching for Sarasota. For him, this World Series title is the highlight of his young lifetime.

jdonalds@projo.com