Santos, the European Tour's rookie of the year in 2012, finished with eight birdies to go with a lone bogey on his second hole. Coming off a fourth-place finish at the Abu Dhabi Championship on Sunday, the 30-year-old golfer from Portugal is looking for his second win on the European Tour.
"Well, I just played really well, especially my short game," the 183rd-ranked Santos said. "I missed a few shots from the tee, but then recovered very well and just kept it like that."
Wall of England shot a bogey-free round that included four birdies on the front nine and a final birdie on the par-5, 18th. Whiteford, of Scotland, had six birdies in a bogey-free round.
"You don't often get Qatar with no wind, so took advantage of it and actually hit the driver for the first time better to give myself a few chances," Whiteford said. "It was one of those days it could have been a lot better almost. A lot of positive stuff, hit a lot of good putts."
Six players including Simon Khan of England were another stroke back in a tie for fifth, and 13 players were another shot back.
Among those were two of the players in the marquee group of the day - former top-ranked Martin Kaymer and fifth-ranked Justin Rose, who just missed out on a playoff Sunday in Abu Dhabi and finished second. Fourth-ranked Louis Oosthuizen, coming off a victory in the Volvo Champions, finished with a 71 after an errant approach shot and some poor putting led to a double bogey on the 18th.
Rose was penalized a shot on 17 when his ball moved on the green just before he was about to putt.