"Penguins center Sidney Crosby was excused from an optional practice Tuesday at Consol Energy Center, but his knee injury doesn't appear to be serious.

Crosby was well enough to stand in the bench area and address a crowd of about 8,000 noisy students from 56 area schools who watched practice.

Coach Dan Bylsma attributed the absence of Crosby and seven of his teammates to a "maintenance day." Bylsma typically allows players with minor ailments to skip practice, especially the day after a night game.

Crosby banged knees with forward Craig Kunitz in the third period of the 3-1 loss to the Boston Bruins on Monday."