GAME, SET AND MATCH! - ZVEREV 7-6 7-5 6-4 KING. Zverev seals the victory with an overhead put-away on his second match point after a tough battle that lasted almost three hours against the world No.168. The German improved as the contest wore on and will be relieved to get through. He'll need to raise his level to live up to the expectation and will face Coric next.
Darian King - Alexander Zverev
US Open men - 29 August 2017
US Open – Follow the Tennis match between Darian King and Alexander Zverev live with Eurosport. The match starts at 01:00 on 29 August 2017. Our live coverage lets you follow all the key moments as they happen.
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ZVEREV 7-6 7-5 5-4 KING. Zverev misses a sitter at the net as King races to a love hold. The German clearly had his mind set on serving it out. Can he finish the job now?
ZVEREV 7-6 7-5 5-3 KING. The 20-year-old No.4 seed seems to lose concentration and allows King a glimmer of hope in a lengthy game. The German is forced to save two BPs before moving to within a game of victory with a classy backhand winner down the line.
ZVEREV 7-6 7-5 4-3 KING. Zverev has a few bites at the King serve, but can't do enough to effectively kill the match here and now. Darian prolongs his stay on Arthur Ashe - for a few minutes more at least...
ZVEREV 7-6 7-5 4-2 KING. No issues for Zverez. He hasn't been tested by King's return game for some time now.
ZVEREV 7-6 7-5 3-2 KING. The Barbadian stays in touch with a much-needed simple hold to 15. Hard to see him launching a fight back now. That first set TB was key for his hopes.
ZVEREV 7-6 7-5 3-1 KING. Zverez consolidates to 15 and has the look of a man who believes victory is within his grasp after a tough slog early on.
BREAK! - ZVEREV 7-6 7-5 2-1 KING. More pressure on the King serve - and this time he can't find a way out of danger. A deft half volley is a delightful way to seal the break for Zverev who is now looking more like the player some are tipping as a dark horse for the title.
ZVEREV 7-6 7-5 1-1 KING. Aces five and six help Zverez to the hold to 30. All square at the start of Set 3.
ZVEREV 7-6 7-5 0-1 KING. Zverev left frustrated as double break point goes begging. Given how tight the first two sets have been he'll have wanted to strike the early blow there after working hard to give himself the opportunity.
SET! - ZVEREV 7-6 7-5 KING. Zverev maintains his focus to serve it out to 15 and take a grip of what has been a surprisingly tight encounter.
BREAK! - ZVEREV 7-6 6-5 KING. Much more patient, mature tennis from Zverev. He's cut down on the errors and King's nerve fails him. A poor choice of a dropshot racks up double break point. The qualifier saves one, but then he fizzes long of the baseline to come unstuck at the last. Zverev will now serve for a two-set lead.
ZVEREV 7-6 5-5 KING. No change as Zverev saunters to another simple hold to move level.
ZVEREV 7-6 4-5 KING. Another rapid service game sees King hold to love. It's not quite the spectacle it was in the opening set with fewer rallies and lively exchanges.
ZVEREV 7-6 4-4 KING. Are we heading towards another tie break? Zverev fires down his third double fault but it's at 40-15 and he duly follows it up with a firm first serve King can't return back into court.
ZVEREV 7-6 3-4 KING. A lovely angled volley gives Zverev his first real sniff of a break, but King slams the door shut and holds firm from deuce.
ZVEREV 7-6 3-3 KING. Sascha with his own love hold. Plenty of quickfire games now, in stark contrast to the lengthy first set.
ZVEREV 7-6 2-3 KING. More classy tennis from King. He likes drop shot and bamboozles the No.4 seed once more on his way to an accomplished love hold.
ZVEREV 7-6 2-2 KING. Sascha has raised his level on serve. He breezes to a hold to 15 to move level.
ZVEREV 7-6 1-2 KING. Still with serve as the world No.168 continues to trade blows with the 20-year-old rising star from Germany.
ZVEREV 7-6 1-1 KING. Zverez finds some much-needed rhythm on his first serve, only coming unstuck once on the point of the game which King took with a delightful dropshot.
ZVEREV 7-6 0-1 KING. Good response from King. Many were expecting him to fade after the blow of losing such a tight first set, but he keeps his focus on earns himself the scoreboard advantage.
SET! - ZVEREV 7-6 KING. A clenched fist from Zverev but he should be heaving a massive sigh of relief instead. It's taken him one hour and 21 minutes to edge out the qualifier 11-9 in an opening set TB. King had two set points, but double faulted on one of them before the German came good on his fourth chance.
TIE BREAK! - ZVEREV 6-6 KING. Nervy moments on both sides of the net. King saves set point and benefits from another unforced error off his opponent to earn himself a real chance in the tie break.
ZVEREV 6-5 KING. Disappointment for King. He's the major aggressor in the game but can't take advantage of four break points. Zverev somehow survives a lengthy test and now King must re-focus to force a tie break.
ZVEREV 5-5 KING. Signs that the No.4 seed is getting agitated. His error count continues to creep up and the cheap points allow a tight King to move level with the hold. Zverez challenges late on the final point and has a difference of opinion with the umpire. The latter was right that he needed to call the challenge earlier than he did.
BREAK! - ZVEREV 5-4 KING. Spoke too soon there! King comes charging back, teasing the errors out of his opponent. Zverev not living up to his billing so far. Not enough consistency and he's leaking cheap errors.
BREAK! - ZVEREV 5-3 KING. It's taken him a while, but it looks like the real Zverev has decided to turn up. He breaks to 15 as King's level dips at the worst possible time. Sascha will now serve for the set.
ZVEREV 4-3 KING. A deep crosscourt forehand sees the German edge in front from deuce after sandwiching his first two aces with a double fault.
BREAK! - ZVEREV 3-3 KING. The No.4 seed is slowly finding his rhythm and breaks back to move level.
ZVEREV 2-3 KING. A gorgeous crosscourt pass and a bullet down the line gives King double break point. He's clearly not read the script. Zverev rallies and saves both before upping the ante to stay just the one break behind.
ZVEREV 1-3 KING. Darian showing no nerves as he fends off Zverev's bid to break back to consolidate from deuce.
BREAK! - ZVEREV 1-2 KING. Huge cheers from those supporting the underdog as he pulls off an unlikely break to edge in front early doors. Zverev looks a bit lacklustre so far and will need to raise his level significantly if he wants to avoid this turning into a real banana skin.
ZVEREV 1-1 KING. The underdog is made to work hard to get on the board as Zverev applies pressure to make deuce from 40-15 down. A first ace puts the Barbadian back in charge and he comes through when his opponent slaps an attempt up the flank into the net.
ZVEREV 1-0 KING. Sascha rattles through a confident and somewhat rapid love hold.
Zverev taking some stick on social media for his attire. He'll serve first.
The players will take to court later than they would have anticipated after the epic tussle between Sharapova and Halep.
The 20-year-old Zverev has never gone beyond the fourth round of a Slam, but with so many big names missing this year he must be hopeful of going far in the draw. The man nicknamed 'Sascha' has already won two Masters titles this season, lifting the trophies in both Rome and Montreal. In contrast, King is playing in the main draw of a Slam for the first time.
The final match on Day 1 of the 2017 US Open sees German No.4 seed, Alexander Zverev take on the world No.168 Darian King of Barbados. The players are due on Arthur Ashe shortly.