A blistering lap from Sebastian Vettel put him half a second clear at the top of the timesheets in second practice for the Monaco Grand Prix as Mercedes struggled for pace.
Vettel's 1:12.720 is the fastest time ever around the streets of Monaco, bettering Lewis Hamilton's best lap from FP1 by 0.7s on the ultra-soft tyres. Daniel Ricciardo and Daniil Kvyat had exchanged times at the top of the timesheets prior to Vettel's new Monte-Carlo benchmark. Vettel initially went fastest on his first lap on the ultra-softs, before making a 0.039s improvement on his second attempt.
2016 Monaco GP polesitter Ricciardo was Vettel's nearest challenger but was 0.487s off the pace. Kimi Raikkonen led the impressive Toro Rosso duo of Kvyat and Carlos Sainz, who appear to be well suited to the high downforce characteristics of the Monaco street circuit and showed strong pace in both practice sessions.
Max Verstappen was sixth fastest ahead of Sergio Perez while Mercedes failed to show its true speed in FP2 as Hamilton and Valtteri Bottas were over a second off the pace in eighth and tenth. Fears over the Mercedes' long wheelbase going into this weekend could be coming true with the Ferrari, Toro Rosso and Red Bull looking much more competitive with their significantly shorter wheelbases compared to the Mercedes.
McLaren enjoyed an encouraging Thursday as Stoffel Vandoorne and Jenson Button were just outside of the top ten. The Woking squad sits bottom of the constructors' championship after five grands prix but it sees Monaco as its best chance of scoring its first points of 2017 due to engine performance not being a key factor at a street circuit like Monaco.
It was deja vu at Williams, which continues to struggle for pace around Monaco. Felipe Massa was only 13th fastest while Lance Stroll's running was cut short by 30 minutes after losing the rear of his car into Casino Square resulting in a hefty impact into the barriers. That brought out the virtual safety car which was soon followed by the red flag. Once the session got back underway once more, teams focused on heavy fuel running.
Nico Hulkenberg made up for a lack of running in FP1 and completed 38 laps on his way to 17th ahead of teammate Jolyon Palmer, whose session ended after seven laps with a technical issue at Portier. Marcus Ericsson and Pascal Wehrlein were separated by just 0.004s in 19th and 20th.
In traditional Monaco fashion, there will be no running on Friday before FP3 and qualifying taking place on Saturday.