Complacency would be understandable. Dustin Pedroia, in his second year with the Red Sox, followed a Rookie of the Year season by winning the Most Valuable Player award. Teammate Kevin Youkilis finished third in balloting for the award.

For two players who had spent their baseball lives defying skeptics, the moment is rather striking. In their amateur careers, scouts defined both members of the right side of the Red Sox infield by their shortcomings.

Pedroia, of course, was too small and had too big of a swing, while also being too slow and too range-deficient to emerge as much more than a utility player. Youkilis was, in the words of his agent Joe Bick (who has watched the Sox first baseman since his high school days in Cincinnati) “barrel-chested.” Scouts pegged him as a bad-body, unathletic player who didn’t hit for enough power.

Both players used the doubts as fuel, both during the season and over the course of the offseason workout programs that have reshaped both players.

“We’ve always had the heart and determination,” said Youkilis, “to become great players.”

Now, the world has recognized the results. So where will the players turn to convince themselves that they still must prove their gifts to someone else?

“I think I might have to remind (Pedroia) that there are still some scouts out there who think he can’t play,” joked Sox G.M. Theo Epstein, before turning more earnest. “He’s still ticked that we didn’t get back to the World Series and win it again this year. Being more a team player than anything else, that’s going to be his driving motivation this winter.”

“Talking to (Pedroia) the other day, he’s already talking about spring training and kicking somebody’s (butt),” added Sox manager Terry Francona. “That’s just the way he’s built. He’s going to compete in anything he does, and everything he does.”

The same, of course, is true of Youkilis. He has long acknowledged the grudge that has accompanied him through his career, the near-disbelief that he went undrafted after his junior year of college, and that he lasted until the eighth round of the 2001 draft.

Now, the proverbial chip on his shoulder has taken a somewhat different shape. There are fewer cynics, but the 29-year-old refuses to be content with his accomplishments.

Across the board, his production has climbed steadily in each of his three full seasons in the majors. His average, on-base percentage, homerun total, RBIs and OPS have remained the same or gone up in each of the past two years. Youkilis is driven to continue those upward trends.

“I know he’s not satisfied. He has the drive to achieve more,” said Bick. “I’m not going to look at the statistics that I see out of him right now and assume that those are going to be career plateau numbers for him. What he’s done up to this point doesn’t tell me that. What we’ve seen suggests that he’s going to be getting better.”

The notion is fascinating. Can Youkilis and Pedroia continue to improve on their exceptional seasons? It seems fair to ask whether the two players can sustain their incredible performances in 2008 as they continue their careers. 

There are so few players to whom Pedroia’s accomplishments compare that it is nearly impossible to look into a crystal ball for him. He is just the third second baseman in major-league history to hit 15 homers and steal 15 bases while producing an OPS that was 20 percent better than league average as a 24-year-old.

The other two to accomplish that feat were Hall of Famer Ryne Sandberg, who did so in his MVP season in 1984, and Carlos Baerga of the Indians, who did it in 1993. Baerga turned in two more excellent seasons before his penchant for partying led to a rapid performance decline.

Sandberg, on the other hand, was an All-Star in each of the next nine years, and an MVP candidate in a few of those. Pedroia certainly seems intent on proving that he can sustain a similarly elite course.

“This spring everyone was talking about a sophomore slump. Next year, in 2009, they’re going to think last year was a fluke. I’ve got to go out there and prepare myself to be good again,” he said. “That’s just who I am. I have to try to find a way to have that edge. It makes you a better player. I’ll always have that. It will never go away.”

Like Pedroia, Youkilis represents a rather unusual case, with few other players who fit his mold. He is a late-blooming first baseman whose performance surged as he neared 30.

Before 2008, Youkilis had never had an OPS that was more than 17 percent above league average. As a 29-year-old, he was more than 40 percent (43, to be exact) better than league average.

Other first baseman to fit that profile for a late-career breakthrough include:

--Rays cleanup hitter Carlos Pena, who was insanely good in 2007 and then very good as a 30-year-old in 2008;
--Dolph Camilli, who was league average before commencing a seven-year run of terrorizing pitchers as a 29-year-old; and
--Bill Terry, whose career went from unremarkable to Hall of Fame material after he turned 28.
 
Camilli and Terry, and even to a lesser degree Pena, offer reason to believe that a breakout season at Youkilis’ age is a rare but sustainable phenomenon. But there are so few players who fit the corner infielder’s profile that it seems difficult to say what might happen.

The only known quantity is both Pedroia and Youkilis will remain driven to build upon this year of incredible accomplishment.

Alex Speier is a senior writer for WEEI.com.