The Englishman, ranked 65th on the European Tour, shared the lead at 7-under 135 with Spanish qualifier Pablo Larrazabal (70).
It was a pretty straightforward bunker shot, not very far, that came off perfect, Lynn said. I just played solid.
Lee Westwood(68), Colin Montgomerie (68), Ignacio Garrido (69), Angel Cabrera (70), Peter Lawrie (71) were tied for third.
Larrazabal shared the lead despite four bogeys.
After I made birdies on 3 and 4, I dont know why, I started to hit the ball really bad, Larrazabal said. I couldnt keep the ball on the fairway.