Veteran Miguel Angel Jimenez was one of three players to earn a share of the lead at the European Masters on Thursday.
The 53-year-old, already the oldest winner on the European Tour, shot a 64 to join Tyrrell Hatton and Scott Hend on six under at the picturesque Crans Montana course.
Spaniard Jimenez won this event in 2010 and Hend also has history here, having lost out to Alex Noren in a play-off last year.
Noren got round in level par, leaving himself with plenty of work to do to retain his title.
Hatton, meanwhile, appears to have rediscovered his game after enduring a run of six missed cuts at his last seven tournaments.
Co-leader Jimenez was pleased to get a low score in the bag to put himself in contention in Switzerland.
"Six-under-par 64 is amazing," he said. "I'm playing very well. I woke up very early this morning and got the profit of that. I'm playing solid, I'm feeling nice and motivated.
"The pin positions are very fair. In these conditions they are holding very well. It's not a very long course and they need to put up some kind of defence."
The leading trio have plenty of competition, with a group of six players just a stroke back and another five within two.
Lower down the leaderboard, Lee Westwood marked the start of his 500th European Tour event with a modest 71, while amateur duo Luca Denk and Hugo Rouillon endured miserable day as they signed for 82 apiece.