When Roger Federer peers over his shoulders to scout out his nearest rivals for Wimbledon glory, the sight of Novak Djokovic will irk him more than most. Federer’s Wimbledon preparations suffered an unexpected hitch on Sunday when he fell to Borna Coric in the Halle Open final, with the three-set defeat putting an end to the 36-year-old’s 20 game run on grass. It also saw Rafael Nadal wrestle the world No 1 spot back off Federer, and though the Swiss will be seeded first at Wimbledon, the loss in Germany removed his cloak of invincibility and served as a timely reminder to his nearest competitors that the upcoming major will be no walk in the park. The 20-time Grand Slam champion brushed off a first-round Stuttgart defeat to Tommy Haas last year before winning Halle and Wimbledon without dropping a set, but on this occasion, Federer must digest the defeat to Coric without an opportunity to correct matters on-court before the Grand Slam gets underway on Monday. And as Federer waits for Friday’s draw to map out his route to the final in SW19, there will be a handful of familiar names further down the rankings that he will be hoping to avoid in the earlier rounds. For one, there’s Andy Murray, who is set to return for his first Grand Slam in a year, and with the two-time Wimbledon champion out at world No 156, the fact he will be unseeded for the tournament means he could prove a first-round opponent for any seeded player, including Federer. Now imagine that for a first-day Centre Court showdown. The same applies to Stan Wawrinka – world No 225 but a three-time Grand Slam champion like Murray – but it’s the prospect of facing Djokovic as early as the last-16 stage which will have Federer feeling most uneasy.