Austria's Matthias Schwab and Frenchman Mike Lorenzo-Vera shared a one-stroke lead after carding seven-under-par 63 in the European Masters first round in Crans Montana on Thursday.
Schwab had set the clubhouse target with seven birdies, five of which came on the front nine, before Lorenzo-Vera caught up with a scintillating back nine which included four birdies and an eagle on the 14th hole at the Crans-sur-Sierre Golf Club.
Lorenzo-Vera, who had recently got married and moved house, credited his psychologist for clearing his head.
"I'm very happy because I just had five weeks off," Lorenzo-Vera said. "It was a stressful five weeks with a wedding and moving plus two kids. I managed to bring the head together pretty well today.
"The best thing to do is to have a very, very good psychologist that you call often. I'm not kidding, that's really what I do. Try to clean the head as much as possible outside the tournaments, and come here fresh and ready to play golf."
Finland's Mikko Korhonen, who had two eagles, Sweden's Sebastian Soderberg and Italy's Lorenzo Gagli were tied for third - one stroke behind the leaders.
World number two Rory McIlroy is the best of the Irish on three-under. He bogeyed three holes to finish four strokes adrift of the leaders.
Padraig Harrington started with a one-over 71, two shots ahead of compatriots Gavin Moynihan and Paul Dunne.