Lap 46: But Maldonado is going quicker without it! He posts 1m45.379s - his best so far - and remains in a lonely 14th place.
Lap 46: Alguersuari has caught Senna and the battle for 15th is over quickly, as the Spaniard breezes past down the long back-straight.
Lap 46: Kobayashi has been lapping consistently quicker than Sauber team-mate Perez over recent laps. They are tied together in 10th and 11th.
Lap 47: Webber is quickly moving clear of Rosberg but needs some rapid laps to avoid falling behind Massa again when forced to make a final stop.
Lap 47: Kobayashi moves through and Perez does not fight that one. The Japanese can now try and bridge the 10 second gap to di Resta.
Lap 47: But di Resta senses danger and again posts his best lap of the race so far. He extends that gap to 10.5 seconds.
Lap 47: Webber does have a significant pace advantage over Massa at this stage, with the second Ferrari also struggling for speed on hard rubber.
Lap 48: Button is now right with Rosberg, who is still to make his second stop in the Mercedes.
Lap 48: Rosberg finally heads in for a late change to the harder tyres.
Lap 48: Kobayashi in 10th posts 1m43.521s and closes the gap to di Resta to 9.7s. Behind them, Perez is dropping away quickly in 11th.
Lap 49: Rosberg resumes in sixth, just ahead of Massa... who has spun away a lot of time with an off at Turn 1.
Lap 49: Barrichello is 12th with Petrov 13th, Maldonado 14th, Alguersuari 15th, Senna 16th, Kovalainen 17th, Trulli 18th and Glock 19th.
Lap 49: Webber, who sets the fastest lap again, will profit from that Massa mistake to end up ahead of the Brazilian after his late stop.
Lap 49: Kobayashi is able to catch di Resta at half-a-second per lap, but he does not have enough laps left to mount a significant challenge.
Lap 51: Five laps remain at Yas Marina.
Lap 51: Button is clocked 9.7 seconds behind Webber, which is comfortably enough to stay ahead of the Red Bull when it makes a late stop.
Lap 52: Perez could be where the on-track action is in the closing laps. He continues to lose pace in 11th and Barrichello is now just 5.4s back.
Lap 52: Barrichello cuts a big chunk out of that gap and is now 2.8s behind Perez. This is a developing fight for 11th.
Lap 53: Perez has smacked into one of the bollards and that will not help his cause. Barrichello continues to close him down.
Lap 53: Meantime, Daniel Ricciardo's drive ahead of his team-mate has come to an end. He pulls off to the side of the track and is out.
Lap 53: Webber is still to make his move to hard rubber, with Red Bull likely planning a stop heading into the final lap. He will end up fourth.
Lap 54: Di Resta is trying his best to hold off Kobayashi. The gap between them is 6.6s, while further back, Barrichello is now just 2,2s behind Perez.
Lap 54: Kobayashi pulls in another second and the gap between di Resta (ninth) and Kobayashi (10th) is down to 5.5 seconds.
Lap 55: Hamilton leads by a comfortable 8.4 seconds as he begins the final lap.
Lap 55: Barrichello is just 1.6s behind Perez and may just get an opportunity on the final lap. This is for 11th.
Lap 55: The Red Bull crew spring into action to change Webber's tyres.
Lap 55: Webber resumes for his single lap on the hard rubber but falls behind Button for the final tour.
Lap 55: Perez in 11th now has Barrichello on his tail.
Lap 55: Hamilton heads under the Yas Hotel for the final time and is on course for a fine victory in the UAE.
14:40 Lewis Hamilton wins the Abu Dhabi Grand Prix!