Santos received an invite to the tournament from sponsors BPI
FIRST ROUND LEADERBOARD:
-6 R Santos (Por)
-5 N Begay III (USA), P Baker
-4 D Vancsik (Arg), R Jan Derksen (Ned), M Kaymer (Ger), M Vibe-Hastrup (Den)
Portugal's Ricardo Santos holed seven birdies in a six-under-par round of 66 to lead by one stroke after the first round of the Madeira Islands Open.
The 24-year-old was one-over after four holes but birdied five in a row around the turn to move ahead of the field.
He finished one ahead of Briton Peter Baker and American Notah Begay III.
Dutchman Robert-Jan Derksen, Germany's Martin Kaymer, Daniel Vancsik of Argentina and Dane Mads Vibe-Hastrup share fourth place on 68.
Twelve players had still to complete their first rounds when play was suspended because of the fading light and earlier hold-ups caused by low cloud.
England's Oliver Wilson, who lost a play-off for the Johnnie Walker Classic in Thailand earlier this month, was six under and joint leader with five to play, but bogeyed four of them for a 70.
It's a good start, but I know I still have a lot to do
Defending champion Jean Van de Velde ended with a 75.
Santos has only been a professional for a year and missed out on qualification for the European and Challenge tours.
But he performed well on his second appearance at the Madeira tournament.
"It's a good start, but I know I have a lot to do," he said.
"It is hard to make the move from amateur to professional, but I have practised and practised to help me with my ambitions."
Baker, 39, who played in the 1993 Ryder Cup and is a triple European Tour winner, made a fast start to his season by picking up four shots in the first six holes.
He said: "For the last few years I've been struggling, not enjoying my golf at all.
"But I had the winter off, thinking things over, making a few changes and that has allowed me to wipe the slate clean and start again."