It was the Briton who started the better and he cranked up the pressure in game five, forcing a breakpoint, before earning another chance two games later.
Berdych was soon serving for the match and the pressure appeared to have got the better of him as Federer saved a match point and brought up a break-back point.
Myler kicked the extras to reduce the deficit to one point and Jim Mallinder's side then started to pour on the pressure as the game began to break up even further.