Kaymer took a one-stroke lead at 9-under 204 despite carding only an even-par 71 thanks to a fade by second-round leader Canizares, who double-bogyed the 16th and 18th holes.
Canizares (73) finished tied for second place with Steve Webster (70) at 8-under 205.
He still held the tournament lead at minus-10 after double bogeying the par-three 16th. But after parring the 17th hole, Canizares landed in the water on 18 en route to yet another double-bogey, knocking him from the lead.
Miguel Angel Jimenez (66), Luke Donald (67), Damien McGrane (67), Francesco Molinari (68), Jyoti Randhawa (70) and Robert-Jan Derksen (72) ended the third round tied in fourth place at minus-7.
The round began 4 1/2 hours late due to rain.