Robert Coles (Getty Images)
England's Robert Coles made the ideal start in his battle to retain his European Tour card when the Portugal Masters got under way.
Coles is currently 164th in The Race to Dubai with only the top 110 after next week's Perth International keeping their full playing privileges for 2014.
The 41 year old has managed just one top-20 finish all season - in the first event in South Africa which was reduced to 36 holes due to bad weather - but found himself top of the leaderboard with four birdies in his first five holes at Oceânico Victoria Golf Course.
Coles, who is still looking for his first victory in more than 360 events, picked up shots at the first, second, third and fifth to lead by one shot from Ryder Cup star Francesco Molinari, Wales' Jamie Donaldson, England's David Lynn and Sweden's Alex Noren.
Scotland's Chris Doak, who is 112th in The Race to Dubai, was a shot further back on two under alongside Spain's Jose Manuel Lara, who is also struggling to keep his card at 158th in the standings.
Defending champion Shane Lowry has no such worries after a consistent season that includes a share of third place in the Alfred Dunhill Links Championship a fortnight ago, but the Irishman was four off the pace on level par.
Lowry bogeyed his opening hole, the tenth, after a poor drive but birdied the 14th to repair the damage.
Coles reached the turn in 31, four under par, before making a blistering start to the back nine with birdies at the tenth, 11th and 12th.
At that point he was three clear of the field but a first bogey of the day on the 13th dropped him back to six under, two ahead of Donaldson and Scott Jamieson.
Donaldson had covered the back nine in 32 with four birdies and no bogeys, while Jamieson had also started from the tenth and picked up shots at the 12th, 13th, 15th and 17th.
Things quickly went from bad to worse for Coles, who found water off the tee on the 14th to run up a double-bogey six that dropped him back to four under.
Donaldson was quick to take advantage with a birdie from 25 feet on the third taking him into the outright lead, although he was soon joined on five under by Jamieson, who birdied the same hole from much closer range a few minutes later.