They came in hyped to the hilt, not just by others, but even themselves.
"I've always wanted to be on a team that won 100 games," said Josh Beckett on one of those optimistic sunny days in Fort Myers, Fla., back in February. "I feel like this team has a chance to do something really, really special like that, and I think that's where some of the determination comes from."
Special seemed possible at times, particularly the glittering middle stretch of the season, when the Sox went 81-42 from April 16-Aug. 31 and sure looked like they might be the best team in baseball.
But the beginning (2-10) and end (7-20 in the final month) were wildly disappointing, sending the hype to a crashing halt and making the Red Sox the first team in baseball history to hold a lead of nine games in September and fail to make the postseason.
"I think we have to accept the three phases of the season for what they were," said Sox general manager Theo Epstein. "We got off to a really bad start. I think we've identified some of the reasons for that. Some of it, we'll probably never know. And then we played great for about four months. We went 81-42. I think we were the best team in baseball. I think that period represented sort of us at our best, our true talent level without any real issues dragging us down. And then obviously September, 7-20, as bad as you can get. We'll be dissecting that phase of the season forever."
In 2010, it was easy to pinpoint why the Sox didn't make it to the postseason. Injuries, from Jacoby Ellsbury to Dustin Pedroia to Kevin Youkilis to Beckett, simply crushed them. And while there were some health problems in '11 -- Youkilis and Clay Buchholz -- the Red Sox had plenty of talent left on the roster to still be playing.
"I don't think it's appropriate for excuses. We did that to ourselves," Epstein said. "We have to take full responsibility for it. We have to own it. Sure, certain things didn't go our way but every team deals with that. We can't run from this. This happened and we have to learn from it and get better."
As tough as the season was, there were some things to remember. Ellsbury had a monster season, perhaps an American League Most Valuable Player Award type of year. Pedroia came all the way back from a broken left foot and was a relentless force. Jonathan Papelbon had a big bounceback in the closer's role, making it more possible that he will be retained as a free agent.
The dark final hours, which included a parting of ways with manager Terry Francona, overshadow a lot of the good things that happened over the course of the season.
And perhaps that bitter taste will help lead to a resurgence in 2012.
"It was a season where we had a really good chance and just didn't get it done," said first baseman Adrian Gonzalez. "That's something to use as, I guess, motivation for next year."
What follows is a quick look back at a 2011 season which was the definition of a roller coaster:
Record: 90-72, third in AL East.
Defining moment: Game No. 162. Everything was lined up for the Red Sox to survive another day. The Rays were losing to the Yankees, 7-0. The Red Sox led the Orioles, 3-2. At that moment, they seemed primed to clinch a postseason berth and wash away the taste of their anemic September. But then came a rain delay in Baltimore, during which the Rays came storming back at Tropicana Field against the Yankees. One strike away from victory against the Orioles, Papelbon had one of his few mishaps of the season and the Sox lost. Maybe two minutes later, Evan Longoria delivered Boston its final blow, hitting a walkoff homer against the Yankees. That meant the Sox didn't even have a one-game playoff to look forward to. They were done for the season, left to wonder exactly how it all went wrong.
What went right: Center fielder Ellsbury didn't just bounce back from his rib fractures of a year ago. He became one of the best players in baseball, a dynamic force at the top of the order who got on base, stole bases and turned into a big-time run producer. Nobody could have predicted Ellsbury would have 32 homers and 105 RBIs. ... Adrian Gonzalez thrived at Fenway, just as everyone thought he would. The first baseman hit .338 and drove in 117 runs. ... Papelbon re-emerged as a ninth-inning force. ... David Ortiz had his most consistent season since 2007. ... Pedroia, even with a screw in his surgically-repaired foot, was a two-way force.
What went wrong: Carl Crawford didn't come close to being the type of player the Red Sox thought they were getting when the Sox signed him to a seven-year, $142 million deal in September. It was somehow fitting that the season ended on a fly ball to left that Crawford slid for, and was in position to catch, but dropped. ... If John Lackey's first season with the Sox was disappointing, his second was a near disaster. The big righty's 6.41 ERA is the worst in club history for a pitcher with at least 150 innings. ... Jon Lester and Beckett, the co-aces of the team, faltered in September when the Red Sox needed them most. So, too, did setup man Daniel Bard.
Biggest surprise: Francona always spoke of managing the Red Sox for the short and long term. Nobody could have guessed he would be out as manager less than 48 hours after the season. While Francona initiated the speed of his exit, the parting seemed to be mutual. Whoever replaces Francona will have a big task ahead of him. Not only will that manager have big shoes to fill -- Francona guided the club to its first two World Series championships since 1918 -- but he'll have to repair what was a divided clubhouse by the end of the season.