ABU DHABI (REUTERS) - Jordan Spieth featured in a six-ball on his last green in fading light at the Abu Dhabi Championship on Saturday as he became one of the few golfers to finish a fog-interrupted third round.

It will now allow the world No. 1 extra rest ahead of Sunday's finale, with the 22-year-old American three strokes adrift of five players who are sharing the lead and have yet to complete 54 holes.

Spieth toiled his way to a one-over 73 in the morning but improved in the afternoon, making four birdies in an error-free third round to shoot a 68 for 209, seven under.

World No. 3 Rory McIlroy, American Rickie Fowler, Ian Poulter of England, Dutchman Joost Luiten and Branden Grace of South Africa are setting the pace on 10 under but all five must return early in the morning to finish their rounds.

"I'm struggling with my alignment on the greens, and with my wedges, so I'm not getting those extra chances but if I have a crazy round tomorrow I have a chance," Spieth told reporters.

The US Masters and US Open champion began his third round on the inward half and was lucky to finish on the ninth hole as two groups of three players teed off together in the gloom, the klaxon signalling the end of play sounding just seconds after Spieth hit his drive.

"I haven't played a six-ball before. We didn't really know what to do," the Texan said.

"We were all very, very relieved to have that happen. It saved us five-plus hours in arriving to the course tomorrow."

Spieth had found the going tough in his second round, unable to recapture the imperious form he showed in winning the Tournament of Champions in Hawaii two weeks ago.

"That happens with long travel and limited practice," he said.

"My short game was there when my tee-to-green play wasn't but then when my tee-to-green was on, I just didn't make any putts."