Roman Safiullin has to take his chances when they appear to him now, and this could be one of them as he opens up a 15-30 lead on the Spaniard's serve.

Martin Landaluce is in the mood, following a wide serve with a ripping inside-out forehand for 15-0.

It's a comfortable hold to 15 for the Spaniard, who also sends down his 14th ace of the match.

Jacob Fearnley surrenders a 40-0 lead but recovers his composure to hold and stay within touching distance in this fourth set.

Carlos Alcaraz isn't having to hit winners. He's just piling enough pressure on Roman Safiullin to force the Russian into missing.

The second seed claws his way back to 40-30, but Safiullin gets the job done in the end.

Pat Cash
Former Wimbledon champion on BBC Radio 5 Live

This has been the tale of the match. Safiullin gets 15-0 or up and then he serves a double-fault or makes an error.

Time is running out for Roman Safiullin and the Russian looks fed up as he sends a forehand long to gift the hold to Carlos Alcaraz.

Jacob Fearnley failed to convert a break point in game two of the fourth set and now finds himself down a break after double-faulting at 15-all and 30-40.

A long way back.

That's as comfortable as it can get for Roman Safiullin at this point. The Russian overhits a backhand, but he makes sure that's the only look in that Carlos Alcaraz gets in his service game and holds to 15.

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Another shake of the fist from Carlos Alcaraz as he backs up the break with a forehand winner after sending Roman Safiullin out wide.

Just three games away from his first win since April.

After falling 30-0 down, Roman Safiullin claws two points back - moving level with a brilliant angled winner as he slides to meet an Alcaraz drop shot.

Carlos Alcaraz is having a much better time with break points than Roman Safiullin. He converts that one at the first time of asking, forcing the Russian to net after swinging a blistering forehand into the corner of the court.

Britain's Jacob Fearnley will have to go the distance to reach the second round of the US Open.

Trailing 1-3 in the third set, Martin Landaluce won five of the next six games - including twice breaking Fearnley - to lead by two sets to one.

Fearnley opened the fourth set with a hold to love.

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Even when he misses, he's smiling. Carlos Alcaraz was only millimetres away from making an incredible round-the-net forehand winner and his reaction is the same as the crowd - 'oooh'.

He's got a break point opportunity now as Roman Safiullin nets.

Another opportunity missed by Roman Safiullin as those three break points come and go, with Carlos Alcaraz able to cling on once again to hold serve.

That's a total of five break points missed by the Russian now.

Roman Safiullin can't win either of the break points, with Carlos Alcaraz pinching the line with a cross-court forehand before he himself misses to take us to deuce.

But he'll get another crack as a booming forehand down the line catches the Spaniard off guard.

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Carlos Alcaraz opens up the door for Roman Safiullin, sinking a forehand into the net to give the Russian a 15-30 lead.

A long forehand from the Spaniard follows and Safiullin will have two shots at an early break.

Carlos Alcaraz just wasn't going away in that point, but Roman Safiullin waits patiently until he's able to dink the ball into the open court and wrap up the hold.

Roman Safiullin has made the most of that break, taking the full five minutes and then some. After changing his shoes, he's finally ready to go.

Carlos Alcaraz isn't show any sign of tiring.

He's bouncing up and down the baseline while he waits for Roman Safiullin to return to the court, as well as soaking up the atmosphere as Dolly Parton's '9 to 5' rings out inside Arthur Ashe Stadium.

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Pat Cash
Former Wimbledon champion on BBC Radio 5 Live

I think Safiullin and his team will be pretty disappointed considering the opportunities that he's had. A chance to break serve in the first set, didn't grab them, broke in the second and then lost a couple of poor games by his standards.

He has not taken any of those opportunities really.

Carlos Alcaraz can't convert the first set point, but he works up another one and this time he gets it as Roman Safiullin fires wide.

The Spaniard swings his fist in celebration and struts back to his chair as Safiullin heads off court for a re-set.

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