But there was more serious business at hand, because Federer was also defending champion in the second of the biggest Masters in the calendar.
He held on to his No1 ranking in Indian Wells, but now needed to reach the quarter-finals to extend his time at the top, even with rival Rafael Nadal absent. And as the Swiss admitted to media ahead of his opening match in the Sunshine State, his biggest incentives after two decades on the tour were staying at No1 and winning titles.
He also admitted in Rotterdam after winning both the title and reaching No1, that totting up 100 titles “would be cool”. He has 97, and was three Championship points from making it 98 in Indian Wells. He would not want to pass up such an opportunity again.
Certainly some of his biggest obstacles to titles in the past would not be giving him trouble in Miami this year: Nadal, Stan Wawrinka, and Andy Murray all missing to rehab from injury or surgery, and the most prolific champion, Novak Djokovic, losing in his opening match as he, too, attempts to come back to his physical peak.
There remained, though, a good number of fellow over-30s who could throw a spanner in the works of Federer’s well-oiled engine. The likes of Fernando Verdasco in the third round and Tomas Berdych in the quarters: both won their openers.
But it was to the younger generation that the Swiss may have cast his eyes in the draw. For recent months had produced increasingly promising performances from the likes of Borna Coric, Daniil Medvedev, Hyeon Chung, Frances Tiafoe, and Andrey Rublev.
In Indian Wells, Federer had played two of the best of them. In the quarters, Chung, up to 23 in the ranks and a semi-finalist in Australia, had brought a lot to the table, and demanded some of Federer’s best tennis to get the straight-sets win.
Then Coric, who beat three top-20 seeds on his way to the semis, won the first set from Federer before losing a nail-biter, 5-7, 6-4, 6-4. The young Croat had knee surgery just 18 months ago, then won his first title in Marrakech, and was back up to 36 in the ranks.
Drawn in the bottom section of Federer’s half in Miami, the fast-maturing Coric found himself in a marathon battle against Argentine Leonardo Mayer, three hours, three sets, and eventually another gutsy win for the 21-year-old, 6-7(5), 6-3, 6-4.
Then there was Alexander Zverev, still only 20, ranked among the top eight for the World Tour Finals last November, and with two Masters titles among a tally of six. He also had two wins over Federer to his name. Here, he played Medvedev, who won his first title in Sydney this year, and this would be the closest of their three matches by far, an exciting three-setter on Miami’s biggest stage in the heat of the day.
The younger of the two, Zverev, was a break down in the first set, levelled and broke again to serve at 5-4. He had to save four break points, one of them via a 39-stroke rally, but eventually took the lead, 6-4.
Medvedev hit back hard and fast, breaking twice, and holding for the set, 6-1. To the delight of the fans, this one would go to the wire, a final tie-break, nip and tuck to its conclusion in Zverev’s favour, 7-6(5). It was the German’s 200th match: He will play his 201st against No28 seed, David Ferrer.
The No5 seed clambered over the net to embrace his opponent in a long and warm exchange, and there had been little between them throughout: 26 winners to 25 in favour of Zverev; 41 errors to 43 by Medvedev; 12 and 13 points won at the net, and 101 and 104 points in the match.
Zverev and Coric could pit themselves against Federer in the semis, but first, the Swiss had to tackle a rather more unknown quantity. Not that the talent of Thanasi Kokkinakis, the 21-year-old from Australia, was in doubt, even though he was currently ranked at 175 and into the second round via a wild card into qualifying.
Why so low? Since the teenage Aussie broke the top 100 almost three years ago, he had had injury after injury, including shoulder surgery at the end of 2015. Even last year ended with injury, so his comeback in 2018 had been cautious via a semi run in the Mexico Challenger. On the main tour? Just two match-wins. But make no mistake: When Kokkinakis fires on all cylinders, the 6ft5ins man is a handful.
In the first set, wthe Australian lacked timing and sharpness—and his potent first serve. He was broken almost before he had settled in the fourth game, and Federer cruised to the set, 6-3, in half an hour.
But come the second, Kokkinakis found the rhythm on his formidable serve, and having survived an opening break point, he looked close to unbreakable. Federer threw in an inexplicably bad service game—a double fault and string of errors—to offer a break to love in the fourth game. He was close to being broken again in the sixth game, too, but survived two break points, 2-4. Another poor backhand error off a second serve from Federer, and the set was as good as done. Kokkinakis threw in four big serves to close it out: 6-3.
The third was the closest of the three, Federer holding with relative ease, Kokkinakis digging deep on serve and powering his forehand at signs of danger. Federer had two chances to break in a 10-minute sixth game, but the young Aussie held firm, even through a time-violation warning. He then offered up two double faults and two deuces in the eighth game, but held.
And although Federer’s serve held up well, errors littered his baseline game, and that would prove his downfall as they headed to a tie-break. Time and again, he hit errant forehands, and Kokkinakis took full advantage. He rubbed salt into the wound with a cracking forehand winner for match point, and served out a famous victory, 7-6(4), after 2hrs21mins. And it earned him not just a place in the third round but the honour of becoming the lowest-ranked player to beat a world No1 in Miami in 15 years.
But talking of No1, Federer will have just one more week to enjoy it. Come the end of the tournament, Nadal will return to the top without playing a match. His residence there may be short: the Spaniard has many titles to defend through the clay swing, Federer none at all. But that is for another month.
For now, Kokkinakis can enjoy a mighty victory, played with focus, confidence and a clear game plan. If he can stay injury free, the world may be his oyster—as it promised to be years ago.
Federer was asked about the new generation of players after meeting two of them in Indian Wells. His words were prescient:
“The young guys are still calibrating their game, understanding what they need to do. There’s a lot of new things to them, like the pressroom and the promotional stuff and sponsors and fans. So there is a lot on their plate—but they will learn, and they’ll get better and eventually push us out—and [smiling] that’s the end for us.”
In Miami, this time, it was just that.
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BIOGRAPHY: Ethan Hazard
BIOGRAPHY: Daniel Sturridge