Ellis, the NBA leader in minutes played, was hurt in the first quarter when a New Jersey player stepped on his right foot. He played most of the second quarter and returned briefly in the third, finishing with a season-low four points with five assists before asking out of the game. He was taken for X-rays, which were negative, but didn't accompany the team on its plane trip to play Phoenix on Saturday.
"I don't think it's anything serious," Nelson said. "I was worried when he went out but the team played real well. Stef Curry kind of took over and managed a real good game and just kind of carried us along, he and [Corey] Maggette."
Ellis had pulled out of a team shootaround on Wednesday due to soreness in his left ankle, and finished Friday's contest making just 2 of 9 shots.
Rookie Stephen Curry stepped in for Ellis with a career-high 32 points.
Ellis averages 26.7 points and 5.5 assists for the year.
Information from the Associated Press was used in this report