Thomas finished tied ninth in the tournament that was won by the player whom he defeated last year in a play-off, Pierre Verlaar Jr of Netherlands.
Verlaar Jr shot his third consecutive round of 70 to finish on six-under par total and will get an opportunity to play the Commercial Bank Qatar Masters later this month.
At Doha Golf Club, another UAE star who was in contention, Christopher Rahm, shot a one-over 73 and finished in third place at one-under par 215, one of only three players to break par after three rounds.
Rahm started strong and was tied with the leader after the first three holes in which he made two birdies, but then had an up-and-down round as he mixed six birdies with a double bogey and five bogeys.
Qatar’s Saleh Ali Musbah Al Kaabi shot the day’s best round of 67 to finish second at three-under par 213.
Speaking to Sport360 from Doha, Rahm said: “Overall, I am happy with the way I played. I enjoyed a lot and played very good golf. The game is right up there and I am competing with some of the top amateurs, which is nice.
“Today, I started well, but unfortunately, a four-putt double bogey on the fourth hole cost me the momentum.
“I was even-par after nine, and was still confident over the back nine as I was just two behind the leader. But I dropped another shot on the 10th and then three-putted the 11th, which saw my chances fade away.
“My driver let me down a little bit today as I missed some fairways and could not set up more birdie chances.”
Thomas, who will be teeing up at the Abu Dhabi HSBC Championship as well as the Omega Dubai Desert Classic, said: “It was just terrible. I lost control of my clubface today.
“I ended up making just one birdie today. The putter also went cold and I had three three-putts for bogeys in the first six holes.
“I have some work to do before Abu Dhabi now, but I am really excited about these next few days. Hopefully, I will play much better than today.”
The two other UAE-based players in the field – Tiago Lobo and Arkesh Bhatia – had a much better finish. Lobo, who stumbled to an 82 yesterday, shot 74 to finish tied 24th, while Bhatia shot an even-par 72 to finish tied 35th.
