Evans does well to get a racquet on another huge Popyrin serve, but the Australian follows up with a cross-court forehand into the corner.

That's good from Evans though. The Briton pops up at the net to guide a backhand volley down the line for a 15-30 lead.

A great reach!

Evans leaps to his right to connect with a volley at the net for 40-0 before bagging a hold to love.

Now, can he make that all-important break...

Laura Robson
Former British number one on BBC Radio 5 Live Sports Extra

It's so frustrating when you play these big servers as you know you are not going to have that many opportunities.

Dan feels as though he's not taken his chances.

This time, Popyrin does hold.

The Australian attacks the point and a volley at the net brings him level at 2-2. A really frustrating one for Evans.

Another break point saved by Popyrin - his seventh in a row.

Can Evans find a way through? A shout of frustration and Evans smacks his racquet at the ground as Popyrin moves to game point again - but Evans composes himself. Deuce number five...

A backhand from Evans sets up break point, but once again Popyrin wins an important point.

A volley then hands Popyrin the chance to finish the game, only for a double fault to cost him. Back to deuce.

Is there to be an opening for Evans in the latest Popyrin service game?

The Australian records two double faults but still leads at 40-30 courtesy of some excellent shot making - however Evans gets himself to deuce.

A bit of movement in the crowd and a technical problem with the scoreboard means the players have to wait a little before things can get back under way...

Still, Popyrin reaches deuce, but Evans finds his serve again to edge back in front in the third set.

Excellent stuff from Dan Evans, who dinks a delicate shot over the net that even Popyrin can't recover. 40-15.

Of course, having said that, Popyrin slices wide and Evans battles back to deuce.

A backhand volley and a final smash then wrap things up for the world number 73 and it's back over to the Briton.

There's no hint yet that Alexei Popyrin's levels are going to drop anytime soon.

The Australian is playing some marvellous shots and another ace takes him to 40-15.

Nicely done. With the pressure building, Dan Evans springs forward to make a volley and secure a hold in his opening service game of this must-win third set.

The winner of this match will meet the winner of the game currently being played over on Louis Armstrong Stadium.

Second seed Daniil Medvedev has taken the first set 6-0 against Spain's Pablo Andujar.

Spanish ninth seed Garbine Muguruza has prevailed on Arthur Ashe in her third round battle with Victoria Azarenka.

The two-time Grand Slam champion beat the Belarusian in three sets, winning 6-4 3-6 6-2.

If Dan Evan is going to make the US Open fourth round for the first time, he's going to have to do it in five sets.

Alexei Popyrin gets himself over the line it's the Australian who is in control on court 17.

Popyrin stays alive with a hefty forehand, before bringing up a set point.

He can't take it and there's still hope for Evans.

A big, big opportunity.

Popyrin hits wide from an Evans slice and the British number one has a break point.

A double fault from Alexei Popyrin and it's 15-30. Half a chance for Evans to get himself back into this.

Laura Robson
Former British number one on BBC Radio 5 Live Sports Extra

Dan has had five break points and only converted one. Even in Popyrin's last service game, he was right in it.