A source told ESPN The Magazine's Ric Bucher on Monday that Harrington will miss at least the next two weeks because of back problems. He has been placed on bed rest for the next week.
Unhappy with his role on the team, Harrington asked to be traded before the season began.
"He thinks he's a superstar. I think he's a very good player. If he wants to be traded, we'll try to accommodate him," Warriors coach Don Nelson told ESPN.com a week ago.
In 11 seasons in the league with Indiana, Atlanta and Golden State, Harrington has averaged 13.0 points and 5.8 rebounds per season. He has never been an All-Star.
He has two seasons remaining on his contract for $9.23 million and $10.03 million.
Ric Bucher covers the NBA for ESPN The Magazine.