The World's top eight players attend the 2017 Nitto ATP Finals Official Launch, presented by Moet & Chandon, at the Tower of London. (L-R) David Goffin of Belgium, Marin Cilic of Croatia, Roger Federer of Switzerland, Dominic Thiem of Austria, Alexander Zverev of Germany, Rafael Nadal of Spain, Grigor Dimitrov of Bulgaria and Jack Sock of The United States pose for a group photo during the The Official Launch ATP Finals at Tower of London on November 9, 2017 (Photo by Alberto Pezzali/NurPhoto via Getty Images)
