Barry Bonds appeared in the episode "Up the Down Steroid" in which he presented the award at the Special Olympics, along with Jason Giambi and Mark McGwire. All three athletes have been linked or allegedly linked to the use of steroids. He reappeared again in "200" and "201".
He appears to have a very large neck, as well as small facial features. He wears his white San Francisco Giants baseball uniform with "BONDS" at its center. He also appears to wear a black and white belt.
Although he wasn't given much screen time, the fact that he appeared to present the awards at the Special Olympics must mean he is somewhat kind.