Sebastian Vettel set the quickest time for Ferrari on a drama-free day of in-season testing at the Circuit de Barcelona-Catalunya on Tuesday.
Vettel moved to the front on the Soft tyres during the afternoon session with a time of 1:23.220 as he finished 0.117s clear of Mercedes rival Nico Rosberg.
Jenson Button was third for McLaren-Honda, having clocked his best time during the morning on the Super Soft compound, with Haas' Romain Grosjean fourth.
Grosjean's quickest time came on the Ultra Soft tyres, which will be used at a Grand Prix for the first time in Monaco.
Pascal Wehrlein was fifth for Manor, in front of Daniel Ricciardo and Pierre Gasly, the latter testing for Toro Rosso after taking the lead of the GP2 Series last weekend.
Alfonso Celis Jr. was eighth for Force India, while Alex Lynn trialled a radical rear wing on the Williams FW38 for a handful of laps in order to gain greater aerodynamic data.
Esteban Ocon was 10th for Renault ahead of his first day in the Mercedes W07 Hybrid on Wednesday.