Pearce joined Derby from Reading in the summer transfer window, but he has made just once appearance for the Rams so far.
His latest display came for the development squad, and Wassall believes the defender is the ideal role model for the younger players at the club to learn from.
"Alex Pearce and Jamie Hanson have both come in from the first team squad and they set the example through their performance," Wassall said.
“They also did it through the way they were in the dressing room beforehand and during the warm-up before the game, whilst their performance and talking on the pitch throughout the 90 minutes was a fantastic.
“Alex has accumulated a lot of Championship experience with Reading and he has come in and set the example."
Pearce has a wealth of experience in the Championship, having represented the likes of Reading, Norwich City and Southampton over the course of his career.
The centre-back is a reliable player who rarely puts a foot wrong, but breaking into Derby's starting line-up will be difficult this season.
The Rams have been very solid under Paul Clement so far, with Jason Shackell and Richard Keogh establishing themselves as the club's first-choice defensive pairing.
Derby have conceded just seven times in their first nine Championship matches, and they currently sit in eighth position in the second tier standings.