Hamilton on top as Rosberg has issues

Lewis Hamilton dominated third practice for the 2014 Formula 1 Italian Grand Prix at Monza, while his Mercedes team-mate Nico Rosberg completed just three laps after encountering a gearbox problem.

Ferrari's Fernando Alonso was 0.412 seconds adrift of Hamilton as he took second place, with Valtteri Bottas just over a tenth further back in third.

Conditions were warmer and sunnier on Saturday with the ambient temperature steady at 23C and the track temperature building slowly from 32C to 36C.

Jenson Button's early flyer, a 1m26.845s set on the hard-compound Pirelli tyres during his first six-lap run, kept him on top of the timesheets until Bottas undercut him by 0.152s.

Alonso and Massa also managed to edge the lead McLaren on pace during similar-length runs, with Alonso matching the 1m26.693 set by Bottas.

Mercedes did not offer a challenge at this point; Hamilton's fastest over a 10-lap first run was 1m27.996s.

A gearbox glitch had caused Rosberg to abort his first eight-lap run early, and a recurrence of the problem when he next went out meant that he only completed three laps before abandoning the session.

Button and Hamilton improved on their second runs, still on the hard tyres, but it was Hamilton who blitzed every sector to return Mercedes to its customary first place with a 1m25.742s.

It was not a flawless run, though; after going quickest he over-ran the first chicane and radioed the pits to inform them that "The brakes don't feel like they're working too well and the DRS isn't working".

Alonso bolted on a set of mediums for his second run and went fastest in the first sector but could not beat Hamilton over the whole lap.

Neither could Hamilton eclipse his own hard-tyre time with his first flyer on mediums during his final stint, as he continued to complain about poor braking performance. Ultimately he improved to 1m25.519s.

Other frontrunners did improve their times on the medium compound by a decent margin in the final minutes, including both the Williams cars - Bottas and Massa jumped to third and fourth, displacing Button to fifth - and the Red Bulls of Sebastian Vettel and Daniel Ricciardo.

The Red Bulls were split by the Ferrari of Kimi Raikkonen, who ran strongly early on completed just 15 laps overall, and Daniil Kvyat's Toro Rosso.

Nico Hulkenberg enjoyed better form in three practice and was sixth fastest for much of the session, closing it out 10th fastest, but his Force India team-mate Sergio Perez lost drive as he accelerated out of the first chicane and came to a halt at the Curva Grande.

Kevin Magnussen struggled with the brakes on his McLaren throughout and finished outside the top 10, over a second off the frontrunning pace.