It's another encouraging sign for Mathieu, dismissed by LSU last August due to substance-abuse issues. A failed test at the combine would have been devastating for the cornerback's draft stock.
Mathieu has been up front about his problems with sobriety during the pre-draft process. That candor was on display when an anonymous NFL assistant coach asked Mathieu how many drug tests he failed in college.
"I quit counting at 10. I really don't know," Mathieu said, according to the coach, who argued LSU is partly to blame: "If he flunked 10 tests before they suspended him, it shows that he got no kind of help."