That’s a better start to the second set from Collins. A winner off either side seals a comfortable hold. She has to try and disrupt Barty’s rhythm before this match slips away.

A brilliant cross-court forehand on the run catches Collins a little static and she frames her return into the crowd. That was Barty at her best and she’s managed to subdue the American so well after a somewhat shaky start. A forehand winner draws more applause from the crowd before an ace clinches the first set in 32 minutes.

Collins makes a nervy start to the game with another double fault and is under pressure on serve again at 30-30. This time the American steadies herself well, though, drawing Barty into an error before a terrific forehand winner ensures the world No 1 will have to serve out the set.

Barty quickly consolidates the break. She races to 40-0 courtesy of more fine serving and another forehand winner. A double fault offers Collins a faint hint of hope but it’s extinguished instantly.

Now it’s Collins whose serve is put under pressure. She’s pushed way behind the baseline by Barty, where the American is not at her most comfortable, and an awkward forehand strays wide. That makes it 15-30 and the crowd senses an opportunity. A fine Barty forehand winner then brings up break point at 30-40 and it’s Collins who cracks first. A double fault hands over the break and that will really help to settle Barty.

Barty looked to be cruising towards another routine hold of serve but, from 40-15 up, she’s taken to deuce by Collins after another huge backhand winner. The world No 1 still seems a little nervous and isn’t covering the court quite as well as normal. A loose forehand then flies way long of the baseline and Collins has break point. Barty rises to the pressure, though, with a high-risk forehand winner that alleviates the danger. She closes out the game with an ace.

There are few signs of weakness from Collins either, though. The American shows all her power and precision in a terrific rally at 0-15, dragging Barty across the baseline and bludgeoning a backhand winner. A no less emphatic forehand winner seals a fourth point in succession and the hold of serve.

Barty races to 40-0 on serve again. The Australian is still warming into her groundstrokes a little but her serve has been as deadly as ever. A forehand drifts long but there’s no trouble as the world No 1 closes out another simple hold.

Collins is equal to it, though. A tame second serve is pounced on by Barty at the start of the game but Collins responds emphatically with a brilliant forehand winner that just clips the line. A service winner is then followed by an unusually tense Barty slice backhand that drifts long. That betrayed a little of the tension that must be there, despite how well Barty conceals it. Collins closes out the game.

An assured start for Barty. The world No 1 races to 40-0, courtesy of three fine serves. She’s pegged back to 30 after a pair of loose backhands but closes out the game confidently.