WHAT HAPPENED: Sloane Stephens ousted the No. 11 seed Dominika Cibulkova in the second round on Wednesday night, 6-2, 5-7, 6-3, in a master class of screaming forehand winners and ripping backstrokes.

Stephens, who missed last year's US Open with a stress fracture in her left foot, won the first set in 52 minutes (including a game that featured 12 deuces) .

Stephens led 4-2 in the second set and was cruising to victory when Cibulkova took control in the seventh game – breaking the 24-year-old American and narrowing the gap, 4-3. Just then, the Slovakian fans at Court 10 came alive, chanting, "Pome! Pome!" But Stephens rapidly quieted them, building a 40-15 lead on Cibulkova's serve. But that's also when she started backsliding.

play video Stephens vs. Cibulkova

Stephens' concentration lapsed, her errors increased, she lost three break points, and suddenly it was 4-4. Stephens regrouped long enough to pull ahead 5-4 and was two points from victory on Cibulkova's serve, but Cibulkova found a lucky break at the end of a long rally when her shot tripped the net cord and went in. Again, in that game, Stephens found herself two points from victory but Cibulkova yanked it away with yet another forehand winner. Cibulkova won that game to tie it at 5, and won the next two to clinch the set, 7-5.

In the third set, no one held serve until the fifth game. Finally, Stephens went up 3-2 on her own serve and, from then on, clinged to the lead. When Cibilkova double-faulted away the next game, Stevens' edge extended to 4-2. Stephens held on in the next game despite facing five deuces.

Finally, at 5-3, Stephens served for the match. She blew her first match point by dumping a cross-court shot into the net, but nailed he next one and – after 2 hours, 41 minutes – advanced to Round 3, where she will face Ashleigh Barty of Australia.

WHAT IT MEANS: Stephens extended her winning record over Cibulkova, the 2014 Australian Open finalist and 2010 US Open quarterfinalist, to 3-1.

MATCH POINT: Will Stephens be the last American standing in women's singles this year?