Tournament host Sergio Garcia claimed a share of the lead after the first round of his belated title defence in the Andalucia Valderrama Masters.
Garcia, who won the last staging of the event in 2011, carded seven birdies and two bogeys in an opening 66 to finish five under par alongside Holland's Joost Luiten.
Fellow Spaniard Pablo Larrazabal and England's Robert Rock were a shot off the lead, but world number five Jon Rahm struggled to a three-over-par 74 in his first professional tournament on home soil.
Irish duo Shane Lowry and Pádraig Harrington both shot opening rounds of one over par, 72, with Lowry enduring the worst conditions in the morning.
As the rain came down the Offalyman was one under on two occasions but three bogeys on his back nine meant he could only sign for one over par but still remains well in the tournament at just six shots off the lead on a notoriously difficult course.
In the afternoon it was a similar situation for Harrington whose three birdies were stunted by four bogeys to leave him in a tie for 39th with Lowry.
With this week being the final regular tournament of the European Tour season, only the top 100 players will secure their full playing rights for next season.
While Lowry and Harrington have nothing to worry about there – they are both still exempt for 2018 – they do have work to do if they are to make it into the European Tour finale in Dubai next month.
With only the top 60 players making it to the DP World Tour Championship, and with neither Lowry or Harrington eligible for next week’s WGC HSBC Champions event in China, a good finish this week would go a long way to booking a place in the desert. Lowry currently sits 65th in the standings while Harrington is 119th.
With no such worries is US Masters champion Garcia who started on the back nine and birdied the 10th, 12th, 15th and 18th to reach the turn in 32, before following a bogey on the first with three birdies in four holes from the third.
At that point the 37-year-old enjoyed a two-shot lead, but a wayward drive on the eighth led to a second bogey of the day as Luiten came home in 31 to join Garcia at the head of affairs.
“It was unfortunately very wet after the rain yesterday and this morning but the course is holding up well and towards the end of the round the ball wasn’t even picking up mud on the fairways,” Garcia said.
“Obviously it was gettable because it was soft but you still have to hit good shots and I was able to do that for the most part of the day. I hit my irons very well and drove the ball well other than on the eighth hole.
“I made some nice putts here and there and overall it was very solid. I’m very happy with my round.”
Luiten, who was second behind Andrew Johnston when Valderrama hosted the Spanish Open last year, also started on the back nine and was only level par after 11 holes, but birdied five of the next six.
“Early on I thought it was playing tough and you have to be patient,” Luiten said. “Finally on my back nine I started to hit some really good iron shots and hit some close for easy birdies.
“I hit four shots within three feet and that makes this game a lot easier.”
Johnston was three under par after eight holes but eventually had to settle for an opening 69, while former Masters champion Danny Willett was a shot behind on one under.
The third Irish player in the field – Gary Hurley – endured a nightmare day as he slumped to a round of 80, nine over par.
Collated scores for Andalucia Valderrama Masters (Irish in bold)
-5: Joost Luiten (Netherlands) 66 Sergio Garcia (Spain) 66
-4: Robert Rock (Britain) 67 Pablo Larrazabal (Spain) 67
-3: Paul Peterson (US) 68
-2: Andrew Johnston (Britain) 69 Richard Finch (Britain) 69 James Morrison (Britain) 69 Ricardo Gouveia (Portugal) 69 Peter Hanson (Sweden) 69 Scott Jamieson (Britain) 69 Ricardo Gonzalez (Argentina) 69 Ben Evans (Britain) 69 Edoardo Molinari (Italy) 69 Oliver Wilson (Britain) 69
-1: Martin Kaymer (Germany) 70 Felipe Aguilar (Chile) 70 Aaron Rai (Britain) 70 Alfie Plant (Britain) 70 Matteo Manassero (Italy) 70 Jason Scrivener (Australia) 70 Anders Hansen (Denmark) 70 Daniel Brooks (Britain) 70 Danny Willett (Britain) 70 Richard Bland (Britain) 70 Lasse Jensen (Denmark) 70
Level: Adrian Otaegui (Spain) 71 Florian Fritsch (Germany) 71 Matt Wallace (Britain) 71 Steve Webster (Britain) 71 Raphael Jacquelin (France) 71 Andres Romero (Argentina) 71 David Law (Britain) 71 Paul Waring (Britain) 71 Justin Walters (South Africa) 71 Robert Dinwiddie (Britain) 71 Andy Sullivan (Britain) 71 Gonzalo Fernandez-Castano (Spain) 71
+1: Alejandro Canizares (Spain) 72 Oliver Fisher (Britain) 72 Shane Lowry (Ireland) 72 Lee Slattery (Britain) 72 Stuart Manley (Britain) 72 Thomas Detry (Belgium) 72 Pádraig Harrington (Ireland) 72 Ashley Chesters (Britain) 72 Chris Hanson (Britain) 72 Filipe Lima (Portugal) 72 Wu Ashun (China) 72 Soren Kjeldsen (Denmark) 72 Simon Khan (Britain) 72 Marcus Armitage (Britain) 72
+2: Sebastian Soederberg (Sweden) 73 Mark Foster (Britain) 73 Carlos Pigem (Spain) 73 Mikko Korhonen (Finland) 73 Marcel Siem (Germany) 73 Austin Connelly (Canada) 73 Nathan Kimsey (Britain) 73 Jorge Campillo (Spain) 73 Bradley Dredge (Britain) 73 Jamie Donaldson (Britain) 73 Laurie Canter (Britain) 73 Jens Fahrbring (Sweden) 73 Sean Crocker (US) 73 Ignacio Elvira (Spain) 73 Anton Karlsson (Sweden) 73 Wade Ormsby (Australia) 73 Julian Suri (U.S.) 73
+3: Jon Rahm (Spain) 74 John Parry (Britain) 74 Simon Dyson (Britain) 74 Damien Perrier (France) 74 Craig Lee (Britain) 74 Eduardo De La Riva (Spain) 74 Matthew Nixon (Britain) 74 Alexander Knappe (Germany) 74 Andrea Maestroni (Italy) 74 Alvaro Quiros (Spain) 74 Nino Bertasio (Italy) 74 Romain Wattel (France) 74
+4: Gary Boyd (Britain) 75 Joakim Lagergren (Sweden) 75 Chris Paisley (Britain) 75 Jamie Rutherford (Britain) 75 Michael Jonzon (Sweden) 75 Duncan Stewart (Britain) 75 Gregory Bourdy (France) 75 Pontus Widegren (Sweden) 75 Sebastien Gros (France) 75 Samuel Del Val (Spain) 75 Zander Lombard (South Africa) 75 Connor Syme (Britain) 75 Bernd Ritthammer (Germany) 75 Pep Angles (Spain) 75 Richard Green (Australia) 75 Niclas Fasth (Sweden) 75
+5: Maximilian Kieffer (Germany) 76 Romain Langasque (France) 76 Daniel Im (US) 76 Rafael Echenique (Argentina) 76 Steven Tiley (Britain) 76 Niclas Johansson (Sweden) 76 Robert Karlsson (Sweden) 76 Gary Stal (France) 76 Joel Stalter (France) 76 Mikko Ilonen (Finland) 76
+6: David Howell (Britain) 77 Gary King (Britain) 77 Stephen Gallacher (Britain) 77 Johan Edfors (Sweden) 77 Jose Maria Olazabal (Spain) 77 Tom Lewis (Britain) 77 Scott Henry (Britain) 77 Renato Paratore (Italy) 77
+7: Alexander Bjoerk (Sweden) 78 Paul Maddy (Britain) 78 Alvaro Velasco (Spain) 78 Sam Walker (Britain) 78
+8: Julien Quesne (France) 79 Magnus Carlsson (Sweden) 79 Gregory Havret (France) 79
+9: Gary Hurley (Ireland) 80
+10: Johan Carlsson (Sweden) 81 Jordi Garcia Pinto (Spain) 81 Marcos Pastor (Spain) 81
