Dyson will go after his seventh European Tour victory in Sunday's final round with Soren Kjeldsen and Pablo Larrazabal teeing off in second place.
Dyson bogeyed the first and 13th holes Saturday and double-bogeyed 18, but in between he carded five birdies to bring his score for the tourney to five-under 211.
Second-round leader Gregory Bourdy fell apart with an 8-over 80 and slid to 24th place.
Saturday's round was delayed nearly 2 hours due to bad weather.
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