LONDON -- The ATP Tour Final is set, and few would have predicted David Goffin to be facing Grigor Dimitrov in Sunday's last match of the tennis season.
While Goffin stunned Roger Federer in Saturday's first semifinal, Dimitrov had to go the distance to beat Jack Sock. It sets up a rematch of the round-robin encounter when Dimitrov swept to a 6-0, 6-2 victory last Wednesday.
Here, ESPN analyst Brad Gilbert breaks down where the final will be won and lost:
David Goffin
Ride his luck: "You almost think that Goffin is playing with house money. He got routed by Dimitrov the first time here and now he has a second chance."
Believe in himself: "After beating three top-five players this week in Rafael Nadal, Dominic Thiem and Federer, he needs to keep things the same and not be tempted to change things up. He should continue to take time away from his opponents and try not to overplay. He found himself in trouble against Federer when he did that, so he needs to stay within himself."
Focus on serve: "This will be the key shot for the Belgian. He hit 14 aces in his win against Nadal and his second serve sped up to good effect against Federer in the second and third sets."
Grigor Dimitrov
See it simply: "He has to think of the final as a one-match situation and not as the chance to win the title of his career, or that he's owned Goffin already in the tournament."
Be an opportunist: "He's going to finish the year close to the very the top of the rankings, yet in the middle part he was really struggling. He's taken advantage of a good situation and is playing his best tennis of the year right now."
Execute, execute, execute: "He needs to use his slice, use the spin he puts on the ball, and he also has to get free points with his serve. It's his variety of shot that will give Goffin trouble."
Gilbert's verdict:
"It's going to be a lot closer than their last meeting but I'm going with Grigor, finishing something like 6-4, 7-6. Hopefully it's a good match but it feels more like a tight two-setter."
Goffin achieves rare Federer-Nadal double
David Goffin became the sixth member of an elite group of players in the men's game with his dramatic defeat of Roger Federer in Saturday's semifinals.
The Belgian joined Novak Djokovic, Andy Murray, Juan Martin del Potro, David Nalbandian and Nikolay Davydenko as the only players to have beaten both Federer and Rafael Nadal in the same tournament.
Goffin saw off Nadal in the round-robin stage at the O2 Arena in London on Monday, with the Spaniard quitting the ATP Finals afterward, saying it was a "miracle" he had made the match so competitive because of tendinitis in his right knee.
It was Goffin, however, who was the player wearing tape around a knee -- his left -- and Nadal's complaints should not detract too much from the achievement.
Goffin had previously failed to beat either Federer or Nadal in eight attempts (six versus Federer, two against Nadal), and afterward claimed the Federer win was the best of his career.
Nadal managed to play for more than 2½ hours against Goffin, too, and didn't withdraw until after it. An asterisk against the Goffin double would be pretty harsh.
A moment @David__Goffin will never forget...
— Tennis TV (@TennisTV) November 18, 2017
Roger Federer: defeated. #NittoATPFinals pic.twitter.com/XPCLt1e8Gy
Final swoon for Federer fans
Fans travel from far and wide to see Roger Federer play at these finals, and sometimes they must gamble on when is best to buy tickets. There is some comfort in the predictability of when one might catch him in action, though.
At least one follower had made the trip over from India "to see him before he retires," and there was a corner of the O2 Arena on Saturday afternoon decorated by a handful of Swiss flags, with many others flown occasionally around the stadium.
The semifinals were sold out long before it was known who would contest them, so how did they know to get tickets for the David Goffin match? Well, they couldn't with 100 percent certainty, but they must have felt they had a 50-50 shot or better.
Federer had made the final four here 13 times in 14 attempts before the 2017 edition, so that's the semis sorted. He had also progressed nine times without losing a match at the round-robin stage, so once the draw was made, a quick look at the match schedule showed the Saturday afternoon session looked like a great bet.
Getting tickets for the final wouldn't have been a ridiculous gamble, either, even though Federer fanatics would have been disappointed this year. The Swiss has been a winner or runner-up 10 times.
Flying the flag for @rogerfederer at the #ATPWorldTourFinals - he has such global appeal that it's good to be reminded where he's from! pic.twitter.com/snZGrYcWL4
— Leo Spall (@LeoSpallESPN) November 18, 2017
Gandalf falls under tennis' spell
Players looking for a bit of magic to inspire them only had to scan the crowd on the penultimate day of the tournament.
If they had done so, they might have spotted Sir Ian McKellen, the actor who played Gandalf in "The Lord of the Rings," keeping a close eye on them.
The two-time Oscar-nominated British actor is a known tennis fan, having been seen at the O2 and Wimbledon in the past, and was here for the first doubles semifinal. He stuck around for the singles, too, and presumably appreciated the drama of Goffin's surprise 2-6, 6-3, 6-4 win against Federer.
Sir Ian McKellen's keeping a close eye on proceedings...#NittoATPFinals pic.twitter.com/mSeWHliMFk
— Tennis TV (@TennisTV) November 18, 2017
Ticket sales creep above quarter of a million
It has been a mixed year for the season finale in terms of tickets sales. With the final weekend officially sold out, the number of seats sold across the whole event has totalled 253,642.
Passing the 250,000 mark is considered good by organisers and sponsors, but the 2017 figure is markedly down on the four years from 2012 through 2015, when consistently more than 260,000 tickets were sold for sessions at the O2 Arena.
The absence of Andy Murray and Novak Djokovic, as well as other usual good bets to qualify such as Stan Wawrinka, Kei Nishikori and Milos Raonic, and the justified doubts about Nadal's fitness, certainly goes a long way to explaining the downturn.
Mind you, the total figure for this year will be more than 1,000 up on last year, a tournament that had a more than its fair share of excitement and drama as it built to a Murray-Djokovic face-off in the final, which Murray won to secure the year-end No. 1 spot.
It just goes to show how big the appeal of Nadal and Federer is; both were missing last year, with sources saying it was a hard sell as a result.
Where's the love for Shapovalov
Spare a thought for Denis Shapovalov, who was presented with two awards -- the ATP's Star of Tomorrow and Most Improved Player -- after the first singles semifinal on Saturday.
The 18-year-old Canadian made the top 50 in the world rankings in October after starting the year at No. 250, having beaten Rafael Nadal at the Rogers Cup and working his way through qualifying to the fourth round of the US Open.
However, after the drama of the ever-popular Federer going out of the season-ending finale before the final, the arena had emptied significantly, and Shapovalov didn't get the attention he maybe deserved. Still, at least Goffin appreciated what he has achieved this year.
🤜🤛
— ATP World Tour (@ATPWorldTour) November 18, 2017
A little congrats from @denis_shapo to @David__Goffin after the Belgian's win.
➡️ https://t.co/UxMNQRYo07 #NittoATPFinals pic.twitter.com/zXvRvqbPcb
ATP looking beyond 2020 and Brexit
If any of the players have been tuning into or reading the local news while in London, they would have had to try hard to avoid talk of Brexit.
The continuing negotiations with the European Union on the details of the UK's departure from it have been headline news for months and dominate the agenda for a great deal of the time.
British Prime Minister Theresa May has insisted the UK will exit on March 29, 2019, but the future of the ATP Finals will not wait on that coming to pass before deciding if London will continue staging the event.
The O2 Arena has hosted the year-end finale since 2009 and has a deal that lasts through 2020, but the governing body will look to work out if it should stay or move 18 months to two years out, sources have told ESPN. Which means a call on that could happen before Brexit does.