Frenchman Francois Delamontagne and Lloyd Saltman of Scotland set the clubhouse target for the rest of the field at the Madeira Islands Open today.
Delamontagne, 32, has yet to win on the European Tour but carded a first-round score of 68, despite suffering a poor front nine as two birdies were overshadowed by bogeys on the fourth, fifth and eighth holes.
His form improved drastically on the back nine as he made two eagles at 10 and 14, dropping only one shot in between and then adding a pair of birdies.
Saltman, 25, from Edinburgh, looked set for an unspectacular start before he birdied three of the final four holes to join Delamontagne on four under.
The 2005 Johnnie Walker champion Emanuele Canonica finished a shot further back, and Scotland's Alastair Forsyth, who won the Madeira event in 2008, remained in contention after leading the way during the early stages before finishing on one under par after a double-bogey at the 14th compromised his score.
He was joined in the clubhouse on one-under by English duo Gary Lockerbie and Chris Lloyd, as well as Spaniard Carlos del Moral.
Two more Englishmen - Chris Gane and Lloyd Kennedy - had still to finish their first rounds but looked competitive and set to challenge the leaders.