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Here is this week's edition of Tough Call. Who will be ATP No. 1 at the end of 2018 - Federer, Nadal, or the field?

Ready, set, go....

Three Reasons Federer Will Be No. 1 at the End of 2018:

~ He’s done it five times before: Federer was year-end No.1 in 2004, 2005, 2006, 2007 and 2009 (he’s one of just three men in ATP World Tour history to have finished year-end No.1 five or more times - Connors did it five times too and Sampras did it six times).

~ He’s much further ahead of his chief rival Nadal than he was at this point last year: Federer is currently 1640 points ahead of Nadal in the year-to-date race, 2000 to 360, while at this point last year he was 755 points ahead, 2000 to 1245 (and he was 1040 points behind Nadal on the 2017 year-end rankings, so that cushion could be significant).

~ He’s playing (at least) one more tournament this year: Federer’s chances at No.1 were hurt by his light schedule last year, playing just 12 events (while Nadal played 18). But the Swiss has already entered at least one extra event this year (Rotterdam this week).

Three Reasons Someone Other Than Federer Will Be No. 1 at the End of 2018:

~ Nadal isn’t his only competition for No.1: Nadal, the current No.1 who will still be right behind Federer in the rankings even if he takes No.1 in Rotterdam, is one of several players who could make a push for year-end No.1 (No.3 Cilic is just 710 points behind Federer in the race right now, and he’s reached two of the last three Major finals…)

~ He hasn’t committed to clay yet: Last year he skipped the clay court season, including Roland Garros, and missing that huge chunk of ranking points is hard to overcome.

~ It’s been almost a decade since he’s finished a season as year-end No.1: The last time Federer finished year-end No.1 was 2009 - he’s come close since then, finishing year-end No.2 in four of the eight seasons since then (2010, 2012, 2014 and 2017) but never No.1.

OUR EXPERTS WEIGH IN:

STEVE FLINK: Federer

The battle for No. 1 in 2018 will be very similar to what it was last year. It will all come down to Roger Federer and Rafael Nadal. This time, though, Federer will finish at the top. He will pick his spots carefully, avoid the clay, win his ninth Wimbledon and finish the season with a few tournament victories indoors. Nadal will dominate on clay again and capture his eleventh French Open, but will not defend his U.S. Open crown. Federer is going to finish the year at No. 1. The last time he ended a season on top of the rankings was in 2009.

ED MCGROGAN: The Field

If Federer is to finish the season No. 1—should he get there in the first place—he’ll have no room for error, with his condensed schedule. Nadal’s schedule may soon start to look like Federer’s, considering his injury, and he’s already behind the 8-ball in the 2018 race. I’ll go with the field, which in reality is Cilic, Zverev, Dimitrov, Thiem and perhaps another player or two that can take advantage of the many points Roger and Rafa will lose should they not replicate their astonishing 2017 performances.

ASHLEY NDEBELE: Federer

Even though he has a lot of points to defend (he’s the Wimbledon defending champ, and made US Open quarterfinals), I think Federer will end the year as No. 1. The rest of the members of the Big Four are dealing with their respective injury issues -- Nadal might not be able to defend his two Majors (especially the US Open title due to his knee issues), and Djokovic and Murray are still recovering from their surgeries -- which leaves healthy Federer the favorite to take the year-end No. 1.

NINA PANTIC: Federer

The Swiss is poised to take over the top spot any day now, and once he grabs hold of it, he's not going to give it up easily. While Nadal is likely to take back the throne in the clay-court season, Federer will be the favorite on grass and in New York, his second home. As for the rest of the field, they will have to wait until 2019 or beyond, for the top spot to be anyone else's but Federer and Nadal's.

STEVE TIGNOR: Federer

He may struggle to defend all of his Indian Wells and Miami points, but there's room for improvement at the US Open. And while Nadal will likely dominate on clay again, it's starting to look like he's caught the injury bug again.

This Week on Tennis Channel Plus 2/12

ATP Buenos Aires (Feb. 14-18)

-Watch Tennis Channel Plus live coverage of Dominic Thiem and Argentina Open beginning Monday February 12 at 12 p.m. ET.

-Can’t make it to Buenos Aires? Watch every match from the Argentina Open on-demand with Tennis Channel Plus.

ATP Rotterdam (Feb. 13-14)

-Don’t miss extended ATP Rotterdam Court 1 coverage live on Tennis Channel Plus Tuesday February 13 at 6 a.m. ET.

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