Novak Djokovic, Serbia
The world No 1 enjoyed one of the best seasons on record in 2011, winning three majors and 10 championships. He will be watched closely here to see if he has overcome a shoulder injury that troubled him late in the season. He could face both Roger Federer and Rafael Nadal.
Rafael Nadal, Spain
The two-time defending Abu Dhabi champion is ranked No 2 in the world. He won three championships in 2011, including the French Open. He met Djokovic in six finals during the season and lost all six. He could see the Serb again in the final here.
Roger Federer, Switzerland
He ended the 2011 season as the tour's hottest player, reeling off 15 consecutive victories and taking three tournament championships, including the season-ending ATP World Tour Finals. Ranked No 3. Still looking for his first title here; fell 7-6, 7-6 in last year's final to Nadal.
David Ferrer, Spain
He has climbed to No 5 in the world, one slot short of his personal best, from 2007. He won two championships this season, taking him to 11 in his career. The clay-court specialist is making his second appearance on the hard court of Abu Dhabi.
Jo-Wilfried Tsonga, France
He brings a No 6 ranking in his second visit to the capital. He ended the 2011 season strongly, reaching the final at both the Paris Masters and the ATP Would Tour Finals. He ranked No 1 in aces during the season and won championships at Metz and Vienna.
Gael Monfils, France
He climbed to No 7 in the world in July before an injury-influenced dry spell dropped him to No 16 to end the season. He picked up his fourth championship at Stockholm. The 2004 world No 1 junior is playing here for the first time.