By Daniel Chavkin Daniil Medvedev is set to become the No. 1 player in the world. View the original article to see embedded media. Novak Djokovic’s loss to Jiri Vesely in the Dubai Championships quarterfinals on Thursday was more costly than simply losing a match. With the loss, Daniil Medvedev is set to take over the top spot from Djokovic in the ATP World Rankings. It will be the first time in 18 years that none of Djokovic, Rafael Nadal, Roger Federer or Andy Murray will hold the top spot. The last time that someone other than those four players was ranked No. 1 was Andy Roddick in February…