Red Bull Racing continued to dominate preparations for the Singapore GP as Sebastian Vettel finished the weekend’s final practice session at the top of the timesheet.

The championship leader didn’t have it all his own way, however, as the commanding one-second gap on single lap pace he enjoyed yesterday was narrowed to just two tenths as Romain Grosjean mounted a challenge for Lotus. Mercedes too closed in, with Nico Rosberg finishing third, half a second down on Vettel’s time. Mark Webber was fourth in the second Red Bull.

The session developed in predictable fashion with the backmarkers first out on the medium tyre while the front runners held station in the garages.

Toro Rosso’s Daniel Ricciardo set the early benchmark at 1:48.001 but as the 20-minute mark passed Lewis Hamilton brushed that time aside with a lap of 1:46.514.

The Red Bull drivers were winding up, however, and at the halfway point Webber soon took over with a lap of 1:46.220, almost three tenths clear of the Mercedes. Vettel then moved into P2, seven hundredths behind his team-mate as the medium tyre exploration edged to a finish.

The field retired to the garages to make final changes for their qualifying simulations on the supersoft tyre and the first man out on that compound was Grosjean.

On the medium, the Frenchman had been sitting in P4, with a time of 1:46.616, but with the supersoft onboard he went over two seconds quicker to claim top spot.

It didn’t last long, as Vettel powered through. The gap though was marginal, with just 0.191 seconds separating the two. Rosberg then took P3. Webber should have got closer but his run on the red-banded tyre was hampered by traffic.

With Webber fourth, Hamilton took fifth place ahead of Fernando Alonso, whose post-Monza suggestion that Ferrari might struggle on the high-downforce, low-speed street circuit played out as predicted. Sergio Perez was seventh for McLaren, with Nico Hulkenberg an eye-catching eighth for Sauber. The top 10 order was rounded out by McLaren’s Jenson Button and the second Ferrari of Felipe Massa.

2013 Singapore Grand Prix Free Practice Three result
1 Sebastian Vettel Red Bull Racing 1:44.173
2 Romain Grosjean Lotus 1:44.364 +0.191
3 Nico Rosberg Mercedes 1:44.741 +0.568
4 Mark Webber Red Bull Racing 1:44.906 +0.733
5 Lewis Hamilton Mercedes 1:44.921 +0.748
6 Fernando Alonso Ferrari 1:45.257 +1.084
7 Sergio Pérez McLaren 1:45.500 +1.327
8 Nico Hülkenberg Sauber 1:45.876 +1.703
9 Jenson Button McLaren 1:45.890 +1.717
10 Felipe Massa Ferrari 1:45.935 +1.762
11 Jean-Eric Vergne Toro Rosso 1:46.084 +1.911
12 Kimi Räikkönen Lotus 1:46.147 +1.974
13 Pastor Maldonado Williams 1:46.338 +2.165
14 Daniel Ricciardo Toro Rosso 1:46.358 +2.185
15 Valtteri Bottas Williams 1:46.660 +2.487
16 Paul di Resta Force India 1:46.879 +2.706
17 Esteban Gutiérrez Sauber 1:46.893 +2.720
18 Adrian Sutil Force India 1:47.249 +3.076
19 Giedo van der Garde Caterham 1:48.931 +4.758
20 Charles Pic Caterham 1:49.037 +4.864
21 Jules Bianchi Marussia 1:49.182 +5.009
22 Max Chilton Marussia 1:49.982 +5.809