"I've got a little more in my tank than I give myself credit for," she said after the race at Hayward Field.
Gardner says her ankle has been particularly bothersome since the NCAA West regional two weeks ago. And on Thursday after her disappointment in the 200, many were wondering whether she'd even try the 100.
But she poured it on to edge runner-up Octavious Freeman, a sophomore from Central Florida who had the best time in the semifinals. Freeman finished in 11 seconds flat.
In the first race of the day, Stanford junior Kori Carter won the 400 hurdles in a collegiate-record 53:21 seconds.
Southern California senior Reggie Wyatt won the men's 400 hurdles in 48.58, breaking his own personal best.
TCU's Charles Silmon won the men's 100 with a wind-aided 9.89.
NCAA track and field championship
O Utah's Amanda Mergaert competes in the women's 1,500-meter final at 3:19 p.m. (MT) Saturday. Weber State's Amber Henry competes in the 3,000 steeplechase final at 3:57 p.m. For a schedule and live scoring from the meet, visit http://bit.ly/ZwEIL1. To watch the meet online, visit http://es.pn/145ILfz