Practice One: Hamilton leads Button and Ricciardo as Rosberg and Vettel struggle
World Champion completes just four laps before breakdown, with Rosberg also spending time on the sidelines
By Mike Wise at Circuit de Catalunya
Last Updated: 09/05/14 1:29pm
The Mercedes driver lapped the 4.655km Circuit de Catalunya in a time of 1:27.023s to go 0.868s faster than Button, with Ricciardo less than a tenth further back.
Early indications, then, that the gap the early-season pacesetters have enjoyed over their rivals remains very much in tact and that Hamilton, who is looking for his fourth straight win this weekend, is still the man to beat.
The Englishman has now finished P1 in 16 of the 29 practice sessions held so far this season. Team-mate Nico Rosberg still holds the lead of the Drivers' Championship but the German had a troubled session after an overheating ERS battery limited his running to just nine laps.
Likewise, Sebastian Vettel largely remained a spectator - the World Champion completing just four laps before an electrical problem forced him to park his Red Bull at Turn 4.
Ferrari's Fernando Alonso was fourth fastest ahead of Rosberg with Kimi Raikkonen (Ferrari), Kevin Magnussen (McLaren), Pastor Maldonado (Lotus), Sergio Perez (Force India) and Felipe Massa (Williams) completing the top ten.
As usual, the start of the European season brings with it a raft of upgrades, although with teams still concentrating on improving the driveability of their new power units, they're not as prevalent as in previous years.
Ferrari, for example, respectively tried new front and rear wings on the F14 Ts of Alonso and Raikkonen. A new engine cover was also on display while Raikkonen has a new, lower, seating position.
Even so, Alonso sounded pessimistic when asked about his own prospects on Thursday and a one-second gap to Hamilton will hardly inspire confidence in the Spaniard.
Button, who himself said that McLaren have a "good chunk" of upgrades in Barcelona, led the way during the closing moments, although Hamilton at that stage remained resolutely lodged in Mercedes' garage.
The Silver Arrows had run one-two prior to the problem on Rosberg's car and normal service was resumed during the closing moments when Hamilton returned to the track.
Despite backing out of fast laps a couple of times, the 2008 World Champion asserted himself during the closing moments and set the benchmark time as the chequered flag fell.
Second practice starts at 1pm (BST).