Adidas suspended its sponsorship of Tyson Gay after the U.S. sprinter tested positive for doping. On Sunday, Gay pulled out of next month's world championships in Moscow after disclosing that a banned substance was detected in an out-of-competition test in May.

“We are shocked by these recent allegations, and even if we presume his innocence until proven otherwise, our contract with Tyson is currently suspended,” Adidas said in a statement.

“Adidas has a clear policy on doping and drug use,” the company said. “Each of the agreements with our athletes include a clear clause which states that the agreement shall be terminated by Adidas if the athlete is found guilty of the possession or use of drugs or any other prohibited substance by the relevant governing sports body having jurisdiction over the athlete.”

The 30-year-old Gay, the American record-holder in the 100 meters, has been backed by Adidas since 2005. He won the 100- and 200-meters at U.S. national championships last month.