Mercedes appeared to finally throw the shackles off as Lewis Hamilton's on-track talking clashed slightly with his chat earlier in the final day of pre-season testing. Hamilton ended the day just 0.003 seconds adrift of Sebastian Vettel's leading time, leaving the title rivals top of the timesheets for pre-season.
Hamilton clocked 1:16.224 late in the day, with Vettel having managed a 1:16.221 earlier on - both set on the softest C5 tyre - although both set times on harder tyres that, when adjusted for Pirelli's estimated drop-off, may have been even faster.
When facing the media during the lunch break at the Circuit de Catalunya, Hamilton estimated that the Silver Arrows are trailing Ferrari by as much as half a second.
Fuel loads, engine settings and more will remain a mystery, although fans will be enthused by the proximity of their title favourites' headline times as excitement builds for the Australian Grand Prix in two weeks' time.
Ferrari's day ended a few hours early after Vettel was stopped on track by an electrical problem that could not be fixed before the chequered flag, while Max Verstappen also missed out on track-time due to a gearbox issue in the Red Bull.
Valtteri Bottas also put in a hot lap, although three tenths down on his teammate and Vettel, while Danill Kvyat and both Renault drivers, Nico Hulkenberg and Daniel Ricciardo, dipped below the 1min 17secs barrier.
Lap counts were marginally lower than previous days for many teams as a number of short runs were managed, particularly in the morning.
Perhaps a sign of Williams still playing catch-up, Robert Kubica's best time on a one-lap effort was 1:18.993, over a second down on the next best, set by Racing Point's Sergio Perez, and suggesting that the Grove squad have plenty of catching up to do over the coming weeks and months.
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They've had a tough couple of weeks, but from what I've seen, this team is full of bright, hard-working and genuinely great people who are passionate about what they do. Hard not to wish them well. ???? @WilliamsRacing https://t.co/q0OcaWe2TZ — Rob Watts (@robwattsf1) March 1, 2019
Big statement from @LewisHamilton in his press conference a short while ago. He is adamant Ferrari are ahead and believes the gap could be half a second in Melbourne. #F1Testing pic.twitter.com/eR3hTfn25g — Rob Watts (@robwattsf1) March 1, 2019
Lewis Hamilton has just set a lap within 0.003s of Sebastian Vettel's pace-setting time on the C5 tyre with less than an hour remaining of pre-season testing. ???? #F1Testing — Rob Watts (@robwattsf1) March 1, 2019