Lewis Hamilton got his hunt for a second title off to a positive start during the first practice session for this weekend's season finale in Abu Dhabi. Hamilton held a 0.133s advantage over Mercedes team-mate and title rival Nico Rosberg, who he leads by 17 points in the drivers' standings. A first or second place finish will secure the title for Hamilton, and with Mercedes 1.7s clear of the rest of the field he should be confident of his chances even if Rosberg picks up the pace over the rest of the weekend. Williams are expected to be Mercedes' closest rivals, but Valtteri Bottas hit trouble 27 minutes into the session when part of his engine cover came off the car. The large chunk of debris flew off the car on the back straight, forcing Bottas to return to the pits with just eight laps to his name and the eighth fastest time. Team-mate Felipe Massa was down in 13th position with only seven laps after he returned to the pits not long after Bottas with an issue with his car. Fernando Alonso was third fastest as he got his final weekend with Ferrari underway, just over 0.1s quicker than the man who will replace him Sebastian Vettel. Daniel Ricciardo was 0.03s off his Red Bull team-mate in fifth place ahead of the two junior Red Bull drivers Jean-Eric Vergne and Daniil Kvyat in the Toro Rossos. Such was the gap between the Mercedes and the rest of the field, Jenson Button found time to tweet about it as he waited for a problem to be sorted on his car in the garage. McLaren team-mate Kevin Magnussen was 11th fastest by the end of the session, but his car was fitted with several 2015 development parts, including a new front wing. Magnussen was still quicker than Kimi Raikkonen, who could only manage the 12th fastest time. The session also marked the F1 debuts of Esteban Ocon in the Lotus, who was only 0.355s off team-mate Pastor Maldonado and Adderly Fong, who was nearly 1.7s slower than team-mate Esteban Gutierrez. Will Stevens is making his full race debut in the Caterham this weekend, but after a problem at the start of the session only completed 13 laps and was 2.803s off team-mate Kamui Kobayashi.