Madison Brengle stuns erratic Serena Williams in Auckland Classic

Serena Williams crashed out of the Auckland Classic after fellow American Madison Brengle pulled off a 6-4 6-7(3) 6-4 upset in a see-saw second round contest on Wednesday.

Brengle was 1-4 down before the 26-year-old staged a brilliant comeback to run away with the first set against the 22-times grand slam singles champion who had constant trouble with her ball toss in the swirling wind.

Williams was a set and 4-3 down when she made a comeback of her own, breaking with a delicate drop shot and unleashing a running defensive forehand to clinch the tie-breaker and force the decider.

Playing her first tournament since losing to Karolina Pliskova in the semi-finals of the US Open last September, Williams went neck-and-neck with 72nd ranked Brengle before losing in two hours and 13 minutes.