Ryan Harrison and Michael Venus got off to a winning start in Group Eltingh/Haarhuis at the Nitto ATP Finals on Sunday by denting the aspirations of Henri Kontinen and John Peers, who are vying to become year-end No. 1 in the Emirates ATP Doubles Team Rankings.

Eighth seeds Harrison and Venus, this year’s Roland Garros champions and making their debuts at The O2 this week, defeated second seeds Kontinen and Peers 6-4, 7-6(8) in 90 minutes.

Peers came under extreme pressure in his first three service games – resulting in deciding deuce points on each occasion. Harrison and Venus got their reward on Peers’ serve at 4-4, when Kontinen hit a forehand volley into the net.

Harrison and Venus continued to play aggressively and in the ninth game broke Kontinen on a deciding deuce point. However, Venus was unable to close out the match as Kontinen and Peers upped the power level to take the set to a tie-break.

Harrison and Venus were unable to convert match points at 6/5 and 8/7, saving a set point at 6/7, prior to closing out their 19th match win of the season. They now have a 2-1 FedEx ATP Head2Head record against Kontinen and Peers, including a victory at the Western & Southern Open in Cincinnati in August.

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It was Kontinen and Peers’ first loss at the Nitto ATP Finals, which they won last year.

Harrison and Venus’ victory means that Lukas Kubot and Marcelo Melo, who are competing in Group Woodforde/Woodbridge this week, could clinch the year-end doubles team No. 1 ranking on Monday should they win their first round-robin group match.

Hyeon Chung made history on Sunday in Milan, becoming the first champion of the Next Gen ATP Finals. The 21-year-old Korean defeated Andrey Rublev 3-4(5), 4-3(2), 4-2, 4-2 to earn his maiden ATP World Tour title. He completed an undefeated 5-0 campaign in the Italian city, streaking past Denis Shapovalov, Daniil Medvedev, Gianluigi Quinzi and top seed Rublev twice to lift the trophy.

How momentous was Chung’s victory? We dive into the five things to know about the #NextGenATP’s triumph…

(1) Korea’s Newest Champion
Chung became the first player from South Korea to hoist an ATP World Tour singles trophy since Hyung-Taik Lee captured the 2003 Sydney title (d. Ferrero). It was also his first final appearance, with his previous best result (SF) coming in Munich earlier this year. With teenagers Soon Woo Kwon and Duckhee Lee also positioned inside the Top 200 of the Emirates ATP Rankings, the future is bright for the Asian nation.

(2) First Timer’s Club
In his final tournament of the season, Chung added his name to the list of first-time ATP World Tour winners in 2017. He became the eighth to win a maiden title this year and third among the #NextGenATP contingent, joining Marrakech champion Borna Coric and Rublev, who prevailed in Umag. Last year, nine players notched their first crowns.

(3) Comeback Kid
Chung had his back against the wall throughout his stay at the Fiera Milano, but he stepped up in the clutch on all occasions. Three times the Korean found himself in an early deficit after dropping the first set. And three times he muscled his way to victory, including in Sunday’s championship. What makes Chung’s escape acts even more remarkable is that he had rallied from a one-set deficit just twice all year, entering Milan. One of those victories came against Rublev at the Winston-Salem Open in August.

(4) From Maui to Milan
Chung became the sixth player to win on both the ATP World Tour and ATP Challenger Tour this year, joining Ryan Harrison, Yuichi Sugita, Victor Estrella Burgos, Damir Dzumhur and Peter Gojowczyk. In January, he lifted the trophy on the hard courts of Maui, U.S.A., in what was his lone Challenger appearance of the season. It was his eighth victory on the circuit in total.

(5) Overcoming Obstacles
Despite enduring a catalogue of injuries and ailments throughout the year, Chung was the last #NextGenATP standing on Saturday. After withdrawing from Indian Wells with a heel injury, he missed the entire grass-court season due to a left ankle issue and recently pulled out of both Shenzhen and Tokyo with an abdominal ailment. Behind a pair of five-set victories, the 21-year-old was a physical force throughout the week in Milan. Just 10 spots off his career-high of No. 44 in the Emirates ATP Rankings, no ceiling is too high for the Korean.

Quick to distance himself from the resurgent success Rafael Nadal and Roger Federer have enjoyed this season, Alexander Zverev is content to be the chaser on debut at this year’s Nitto ATP Finals, the leader of the baying pack behind the Top 2 in the Emirates ATP Rankings. At just 20 years old, the German is arguably the most hyped of the chasers in 2017.

On Sunday night, he will gain his first taste of competition under the lights of the O2 arena. His opponent, No.5 seed Marin Cilic, has been here twice before, although he will carry nerves of his own having claimed just one of his six matches at the season finale.

View FedEx ATP Head2Head matchup for the Group Boris Becker matches to be played Sunday at the Nitto ATP Finals and vote for who you think will win!
Federer vs. Sock | Zverev vs. Cilic

Of the two rangy 6’6″ frames, it is the German, with his ’70s-style mop of surfie locks, who possesses the better movement of the two. Both employ a similarly aggressive baseline game. While Cilic’s forehand has more pop than his younger opponent’s, it is Zverev’s flat, penetrating backhand which is his money shot. It is a weapon he attributes to his mother Irena’s tuition. 

Both utilise their height effectively on serve and on the O2 Arena’s slick surface, expect it to deliver plenty of free points for both. With the pair comfortable on the fast indoors, much will boil down to which of the two controls emotions better. For Zverev, still searching for a maiden quarter-final appearance in a major, the glare of expectation on such a big stage could spark a few nerves. 

Zverev has raised five trophies this season, including ATP World Tour Masters 1000 titles in Rome and Montreal. Since claiming the Coupe Rogers in August, however, he has won just eight of his 15 matches – a lone semi-final showing from seven events through the Asian and European indoor swings. He will need to find something in reserve to lift for his final event of the season.

Despite a shaky start to the season Cilic crossed off another goal in October when he cracked the Top 4 for the first time. With his fluid serve and impressive net game ideally suited to the slicker surfaces, the Croat carried grass-court form to the All England Club, where he reached his first Wimbledon final. 

On his season-ending return to London, Cilic has reached semi-finals in Tokyo, Shanghai and Basel leading in. While he brings stronger indoor momentum to the clash, he has beaten Zverev just once in four FedEx ATP Head2Head encounters. 

If the German is looking for a psychological boost he may want to draw on an omen. Cilic has lost to the eventual champion in his opening round-robin match in his two prior Nitto ATP Finals appearances – to Djokovic in 2014 and to Murray last year.