Barcelona - British rookie Scott Jamieson eclipsed the Spanish Open field on Thursday with an opening six-under-par 66 at El Prat to lead by a stroke.
Jamieson leads over local favourite Pablo Larrazabal, fellow rookie Romain Wattel of France and experienced tour winners Jeev Milkha Singh of India and Briton Steve Webster.
The 27-year-old Scotsman has made a remarkable transition over two years, elevating himself from the Europro and Challenge tours to become a force on the main tour.
However, despite fifth and sixth places in his nine events, the Augusta State University graduate has been unable to play the last four weeks because of his tour ranking.
However, a trip to visit his fiancée in Jacksonville during his break where he practiced at the Palancia course paid dividends at the tricky El Prat layout.
"My coach told me to get my bad shots under control, no-one needs to make good shots better," Jamieson told reporters after a round that included two 30 foot putts and eight birdies.
Larrazabal's extensive local knowledge stood the Spaniard in good stead as he took the early lead. A member of the club near Barcelona, Larrazabal has played countless rounds at the course designed by Greg Norman and opened in 2004.
"Nobody knows this course better than me," Larrazabal told Reuters after carding a flawless 67.
"I know exactly where to hit the greens. You can be in big trouble if you hit them in the wrong spot."
Larrazabal was watched for a few holes by his brother Alex, the 2002 British Amateur champion, before Alex took up his duties as Ryder Cup captain Jose Maria Olazabal's caddie.
It has been a barren time for Larrazabal since he burst on to the European Tour scene with a dramatic victory in the 2008 French Open as a qualifier.
"For the last five or six months I've been playing very solidly without finishing off in tournaments," he said. "It would be nice to do so here."
One of the tournament favourites, 18-year-old Matteo Manassero, marked his first event back after winning the Malaysian Open with a frustrating 73.
"The greens were very tricky and difficult to read, so I missed quite a few birdie chances," the Italian teenager told reporters.
"Tomorrow I'm going to have better knowledge of the course so I should do better."
Britain's Elliot Saltman, back after serving a three-month ban for breaching rules, returned a 72, opening with a double-bogey but turning his day around by coming home in three-under 33.
Leading first round scores from the Spanish Open at the par-72 course:
Scott Jamieson (Britain) 66
Romain Wattel (France) 67
Pablo Larrazabal (Spain) 67
Jeev Milkha Singh (India) 67
Steve Webster (Britain) 67 68 Gregory Bourdy (France) 68
Peter Lawrie (Ireland) 68
Thomas Aiken (South Africa) 68
Anthony Wall (Britain) 68 69 Anders Hansen (Denmark) 69
Shane Lowry (Ireland) 69
Jesus Maria Arruti (Spain) 69
Seve Benson (Britain) 69
Shaun Norris (South Africa) 69
Christian Nilsson (Sweden) 69 70 Phillip Price (Britain) 70
Danny Willett (Britain) 70
Richard McEvoy (Britain) 70
David Lynn (Britain) 70
Jason Knutzon (U.S.) 70
Chris Wood (Britain) 70
Barry Lane (Britain) 70
Colin Montgomerie (Britain) 70
Lloyd Saltman (Britain) 70
Alejandro Canizares (Spain) 70
Francois Delamontagne (France) 70
Andreas Harto (Denmark) 70