Minneapolis ? Attorneys for the Minnesota Vikings say the diet supplement ephedra contributed to Korey Stringer’s death from heatstroke at training camp in 2001.

The team was responding to a motion filed by Stringer’s widow, Kelci, in her $100 million wrongful death lawsuit against the team, scheduled for trial June 9. Kelci Stringer’s attorney, Paul DeMarco, said the team was trying to smear her husband’s reputation.

In documents filed Friday, team lawyers cited the testimony of Stringer’s roommate, guard David Dixon, who said Stringer had told him that he had taken a supplement containing ephedra on July 31, 2001.

Stringer collapsed from heatstroke later that day, and died the next morning. The NFL discouraged the use of ephedra when Stringer played and banned the substance after he died.

The supplement has been linked to heart attacks, strokes and seizures in otherwise healthy young people.

“Evidence of Korey Stringer’s use of ephedra can be causally linked to onset of heatstroke,” team attorney James O’Neal wrote in papers filed in Hennepin County District Court.