Right...grab some popcorn. This should be a Blockbuster.

SVITOLINA 6-7 6-1 4-6 KEYS. She's done it! From 4-2 down in the third set, Madison Keys hit a stunning purple patch to win four games in a row and make the quarter-finals of the US Open for the first time, at the expense of fourth seed Elina Svitolina. Fantastic performance from the American, particularly after that gruelling second set.

SVITOLINA 6-7 6-1 4-5 KEYS. Three games in a row for Madison Keys, who is a game away from the quarter-finals for the first time.

SVITOLINA 6-7 6-1 4-4 KEYS. What a way to break back! Madison Keys hits another purple patch and sends a series of stinging winners past Elina Svitolina, who is beginning to show signs of nerves. It feels like Keys is in control now and she has Ashe out of their seats.

SVITOLINA 6-7 6-1 4-2 KEYS. Svitolina consolidates the break to extend her lead. Huge pressure now on Keys to hold in this next game.

SVITOLINA 6-7 6-1 3-2 KEYS. Svitolina is turning the screw now, defending robustly and picking her moments to attack Keys. She earns a first break of the deciding set, dampening the party on Ashe a little. Tense moments ahead for Madison Keys.

SVITOLINA 6-7 6-1 1-2 KEYS. The first comfortable hold of this set goes to Madison Keys, who nudges in front in the decider.

SVITOLINA 6-7 6-1 1-1 KEYS. One big hold apiece at the start of the second set, as Svitolina also saves a break point early on in the decider. Suddenly it's hard to take your eyes off this match, which has been a slow burner but is coming to the boil nicely.

SVITOLINA 6-7 6-1 0-1 KEYS. Two breaks point saved brilliantly and Keys holds to get in front in the final set. Given what happened in the second, that was a hugely important game to win for Madison Keys.

SVITOLINA 6-7 6-1 KEYS. Svitolina takes the second set in just 24 minutes, clinching the final game with a 360-degree volley. It goes to a decider.

Can Keys rediscover her poise and her form?

SVITOLINA 6-7 5-1 KEYS. Ah. If only you'd done that sooner, Madison! A near-perfect service game from the American leaves Svitolina serving for the set and ensures that a bagel will not be served this evening.