Unai Emery put his players through their paces at London Colney on Friday

                                                                                       Unai Emery continued to step up the intensity of pre-season training for his Arsenalstars with an exhausting session on the hottest day of the year so far.

The likes of Hector Bellerin, Shkodran Mustafi and Calum Chambers were hardly able to stand come the end of the session with temperatures hitting 30 degrees.

Despite the heat, Emery ensured he got every last ounce of energy out of his players with another gruelling workout at the club's London Colney base.The Gunners took to Facebook to share a video of their players completing a sprinting exercise, writing: 'We knew pre-season was tough... and the boys are being worked HARD'.

Full-back Bellerin can be seen collapsing to the floor the moment he crosses the line as Mustafi and Carl Jenkinson quickly follow suit.

Chambers, dripping in sweat, is also forced to hit the deck as team-mates Rob Holding and Eddie Nketiah shake their heads at the camera on their way to the changing rooms.