Thomas Vanek is at a loss. He just can't explain how a season that started so well for him ended so poorly.

Through the opening 40 games, the Sabres' winger was a goal-scoring, point-producing machine. He put up 19 goals and 40 points to rank near the top of the NHL. The longest he went without reaching the score sheet was two games.

The season started heading south Jan. 7. In the final 38 games of the season, Vanek scored just seven times and recorded 21 points, including two assists in Saturday's 4-3 shootout loss in Boston. He had skids of seven, four and three games without a point.

"I don't know [what happened]," Vanek said. "I really don't know. Obviously, the team went into a little funk, and I needed to be one of the guys to keep going and be a leader. I got trapped right in it."

The prolonged slump has ended Vanek's reign as Buffalo's perennial goal-scoring leader. After leading the team for five straight seasons, he finished second to captain Jason Pominville this year. Vanek scored 26 times, the second-lowest total of his career, ahead of only the 25 he notched as a rookie in 2005-06.

"You look back at some stretches where we could have been better, myself included," he said. "We could have made a difference and got some points and not be in the position we are."