Just 0.088 seconds separated the top three of Ricciardo, Ferrari’s Sebastian Vettel and Verstappen during an eventful and encouraging morning session at the Hungaroring.
Title leader Lewis Hamilton was only fifth fastest but Vettel, on track for the first time since his victory-costing crash on Sunday in the German GP, was less than a tenth of a second behind Ricciardo.
Red Bull, victors at Monaco in May, are optimistic the tight and twisty Budapest circuit will suit their car without highlighting the power deficiency of their Renault engine.
Ricciardo’s benchmark was particularly impressive given it was set on soft tyres – two ‘steps’ slower than the ultrasoft compound which Ferrari used to set their quickest time.
But Ferrari rarely show their hand in Friday practice and it’s likely the Scuderia, whose cars are wearing black ‘armbands’ in remembrance of Sergio Marchionne, their former president who passed away this week, will have kept plenty in reserve.
Hamilton never appeared comfortable on track and twice ran wide, either side of a lengthy set-up change in the Mercedes garage.
Team-mate Valtteri Bottas was sixth in the other Mercedes.
After encountering problems evaluating new car parts in their wind tunnel, McLaren have tended to use recent Friday practice sessions as extended test outings.
But Fernando Alonso was a respectable 12th while team-mate Stoffel Vandoorne, who has changed chassis this weekend, was 16th.
Nico Hulkenberg hit trouble when his car crawled to a halt, ruining what had until then been an encouraging start for Renault. Haas’ Romain Grosjean overtook the German late in the session in the timesheets to be the ‘best of the rest’ in seventh.
Sauber’s Marcus Ericsson, one of several drivers to spin and lock up into the first corner, was slowest of all.
This weekend’s race, live on Sky Sports, is the last of five in six weeks before the summer break.
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