Stenson, who won in Qatar in 2006, had seven birdies at the Doha Golf Club' though the 32-year-old Swede still found a way to critique himself afterward.
Maybe I didnt play my best golf today, but I putted really well, Stenson said. I feel it comes down to putting well when the conditions are as good as we saw today.
Robert Dinwiddie, Anders Hensen, Louis Oosthuizen, Brett Rumford and Lee Westwood were a stroke off the pace on a crowded leaderboard. Six more players were another shot back.
Coltart, who won the Qatar Masters in 1998, had five birdies and an eagle on No. 16, easily the highlight of his day.
It was into the wind, but I managed it, Coltart said. I think I played steady. I gave myself chances. It was nice to get opportunities. I have good memories of this place.
Jimenez had six birdies, including four on the front nine.
Sergio Garcia (70) and 2007 champion Retief Goosen (69) were also in the mix, but defending champion Adam Scott (73) and American Ryder Cup star Boo Weekley (74) struggled.
A six-time Ryder Cup player from England, Westwood was happy with his first significant outing of the season.
I didnt really know what to expect, Westwood said. I started really well with a good drive down 10 and didnt make a birdie. After six holes, I thought it was going to be one of those slow starts of the year where Im a bit rusty, but it all came good in the end.