Top-seeded Roger Federer began his bid for a ninth title at the Gerry Weber Open with a routine 6-4, 7-6 (3) win over wild card Jan-Lennard Struff Wednesday. Federer never faced a break point and fired 15 aces to reach the second round. Second-seeded Kei Nishikori pulled out with a rib injury. Nishikori reached the second round and was due to face Florian Mayer Wednesday but told organizers that he was unable to play. Mayer advanced to the quarterfinals with a walkover. In other first-round matches, eighth-seeded Philipp Kohlschreiber defeated Marcel Granollers 6-2, 7-6 (4), hitting 39 to 24 winners, while Teymuraz Gabashvili beat Paolo Lorenzi 6-1, 6-4. In a second-round match, Alexander Zverev advanced to the quarterfinals when Benjamin Becker retired with a back injury with Zverev leading 7-5, 3-0. Zverev lost the first four games of the match but recovered against his German opponent. Raonic makes winning start Milos Raonic made a winning start under coach John McEnroe as the Canadian third seed fought back to beat Australia's Nick Kyrgios 6-7 (5/7), 6-4, 6-4 at Queen's Club Wednesday. Raonic hired American legend McEnroe as his new coach earlier this month and the pair are working together for the first time at the Wimbledon warm-up event in London. McEnroe, a seven-time Grand Slam champion, has been putting Raonic through his paces on the practice courts at Queen's for several days and the early returns on their relationship look promising as the world number nine subdued the dangerous Kyrgios in a rain-interrupted first-round tie. Raonic will face Czech world No. 68 Jiri Vesely for a place in the quarterfinals. Juan Martin del Potro's decision to skip the French Open in favor of preparing for the grass season backfired as the Argentine was beaten 7-6 (7/2), 6-4 by American seventh seed John Isner. World No. 17 Isner slammed down 25 aces as he booked a second-round clash with Luxembourg's Gilles Muller. British wildcard Kyle Edmund enjoyed the best win of his promising career as he defeated French world number 18 Gilles Simon 6-4, 3-6, 6-1. South Africa-born Edmund is ranked 85 and the 21-year-old's reward for shocking the eighth seed is a second-round meeting with France's Paul-Henri Mathieu, who defeated British wildcard Daniel Evans 7-6 (10/8), 6-7 (6/8), 6-3. Jankovic prevails Second-seeded Jelena Jankovic overcame a first-set humiliation to advance to the quarterfinals of the Mallorca Open Wednesday. The 25th-ranked Serb rallied to beat Belgian qualifier Elise Mertens 0-6, 6-4, 6-3 in their second-round match. Eighth-seeded Eugenie Bouchard of Canada, a former Wimbledon finalist, defeated Anastasija Sevastova of Latvia 6-3, 6-3, and qualifier Sorana Cirstea of Romania ousted Daniela Hantuchova of Slovakia 6-3, 6-4.