Scot Paul Lawrie picked his way through the gloom to lead the Portuguese Open by one shot on Saturday.
GB and Ire unless stated
-11 Pa Lawrie
-10 B Lane (after 15 holes)
-9 P Broadhurst, JF Lima (Por) (both after 15)
-6 S Dodd, A Forsyth
Lawrie carded a 66 to reach 11 under but with three hours lost to rain delays, his closest rivals were forced off the course as darkness fell.
England's Barry Lane was on 10 under after 15, with overnight leaders Paul Broadhurst and Jose-Filipe Lima of Portugal on nine under after 15.
Play was suspended three times because of waterlogging at Quinta da Marinha.
"I can't deny I play better in bad conditions," said Laurie, the 1999 Open champion.
"It's like that at home [in Aberdeen] half the time, so you get used to it. I rather hope the sun shines tomorrow though."
The 36-year-old birdied the third, fourth and seventh to go out in 33, and despite two bogeys inside his last four holes he also grabbed four homeward birdies.
Lawrie, who plummeted to 140th on the European money-list last season, has seen signs of encouragement with a fifth place in the Singapore Masters in January and 13th in the New Zealand Open in February.
Former European Ryder Cup star Broadhurst dropped two shots inside the first four holes but went on a birdie spree around the turn before handing one shot back on the 15th.
Lane endured a mixed round but was left poised to finish one place better than his share of third position after halfway.