View FedEx ATP Head2Head for the following matches from the 2018 Miami Open presented by Itaú & vote for who you think will win! 
Del Potro vs Raonic | Isner vs Chung

[19] Hyeon Chung (KOR) vs. [14] John Isner (USA)
Isner leads FedEx ATP Head2Head series 2-1
Stadium – Not Before 3 p.m.

Hyeon Chung was the man standing across the net, but it was a much different Chung than the player John Isner had faced during their previous two FedEx ATP Head2Head matchups.

Isner had won both of those contests rather routinely, taking all five sets at 2016 Houston and 2017 US Open. But in January at the ASB Classic in Auckland, the two met for a third time, and Chung won 7-6(3), 5-7, 6-2.

Isner walked off the court and said to his coach, “That’s a completely different player than the one I played in the previous two times.”

The American isn’t alone in noticing the drastic improvements Chung has made to his game. The 2017 Next Gen ATP Finals champion was No. 58 in the ATP Rankings when he hoisted the trophy at the inaugural 21-and-under tournament in Milan.

But only three months into the 2018 season, the South Korean is already No. 23, thanks to a semi-final run at the Australian Open and quarter-final showings at the Delray Beach Open, the Abierto Mexicano Telcel presentado por HSBC in Acapulco and the BNP Paribas Open in Indian Wells. He has an 18-6 match record in 2018.

“He’s found the magic potion this year for sure. He’s playing incredibly well,” Isner said.

Isner, according to his own analysis, had his best serving day of 2018 on Tuesday, when he beat second seed Marin Cilic 7-6(0), 6-3 to reach the Miami quarter-finals. The 14th seed hit 12 aces, won 76 per cent of his service points and never faced a break point.

“I served exceptionally well and that’s what kept me in the match and put scoreboard pressure on him, and I finally was able to break through and get a break,” said Isner, the 2015 Miami semi-finalist.

But Chung has also delivered some of his best from the line in Miami. He and fellow quarter-finalist Milos Raonic have not been broken all week. Chung has held in all 26 of his service games and saved all seven break points he’s faced.

[5] Juan Martin del Potro (ARG) vs. [20] Milos Raonic (CAN)
FedEx ATP Head2Head series tied 2-2
Stadium – Not Before 9 p.m.

Just 11 days after beating Milos Raonic 6-2, 6-3 in the BNP Paribas Open semi-finals, Juan Martin Del Potro comes face-to-face with the Canadian once again.

If Del Potro is to extend his 14-match winning streak, he’ll have to attempt to break down the serve of Raonic, who, through three matches in Miami, has held all 28 of his service games and saved all five break points he has faced.

Having dropped to No. 40 in the ATP Rankings on 26 February, his lowest position since No. 59 on 14 February 2011, Raonic has been rebuilding his form and fitness.

As a three-time Miami quarter-finalist (also 2014, 2016), he’ll be looking to break a five-match losing streak against players in the Top 10 of the ATP Rankings. Since beating then No. 9-ranked Rafael Nadal in the 2017 Brisbane International presented by Suncorp quarter-finals, he has lost 12 sets against the elite ATP World Tour stars.

Prior to Del Potro securing his 400th career match win on 17 March against Raonic, the pair had contested three tight two-set battles at the 2013 Rogers Cup in Montreal (Raonic), 2013 Rakuten Japan Open Tennis Championships in Tokyo (Del Potro) and the 2017 Delray Beach Open (Raonic).

Del Potro has won a 2018 ATP World Tour-best 20 matches (20-3 record), with titles at the Abierto Mexicano Telcel presentado por HBSC (d. Anderson) and Indian Wells (d. Federer). Today, he’ll look to reach the Miami semi-finals for the first time since 2009.

Borna Coric is again proving he’s in this for the long haul after a third straight three-set victory to reach the Miami Open presented by Itau quarter-finals, this time over #NextGenATP Canadian Denis Shapovalov. After a semi-final run in Indian Wells, the 29th seed is through to his second straight ATP World Tour Masters 1000 quarter-final with the 7-6(2), 4-6, 6-4 victory.

Brimming with confidence after his run in Indian Wells, where he narrowly fell short against Roger Federer, Coric was more consistent than his 18-year-old opponent to take the opening-set tie-break 7/2. Shapovalov, coming off his best win this season over No. 11 seed Sam Querrey in the third round, found his spark when he picked off a backhand pass from a short approach to bring up three break points at 2-2 in the second set. He converted and despite letting the Croatian back into the set, he closed out the final two games of the set to send the match into a decider.  

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Coric, a qualifier at last year’s Next Gen ATP Finals in Milan, had survived a two-hour, 56-minute clash to defeat Leonardo Mayer in the second round before a two-hour, 49-minute battle to see off No. 8 seed Jack Sock on Monday. This match – a two-hour, 17-minute showdown – seemed almost efficient in comparison. 

The Croatian claimed a 33-shot rally to edge ahead 5-4 in the third set against Shapovalov before the Canadian blinked, sending down three double faults to gift two match points. 
Coric sealed his second FedEx ATP Head2Head victory in as many meetings between the pair and awaits the winner of Tuesday night’s match between fourth seed Alexander Zverev and 17th seed Nick Kyrgios.