Lewis Hamilton topped the timesheets in both Brazilian Grand Prix practice sessions on Friday to lay down the gauntlet to Mercedes team-mate Nico Rosberg.
Hamilton trails Rosberg by 19 points in the drivers' championship and victory for the German at Interlagos would wrap up a maiden title.
However, reigning champion Hamilton has won the last two races and showed good pace as he prepared for the penultimate round of the 2016 season.
The sessions were held in hot and sunny conditions, but rain is expected later in the weekend and could have a big say in Sunday's race.
Hamilton set the pace in FP1 with his time of one minute and 11.895 seconds, with Rosberg down in third behind Red Bull's Max Verstappen.
Red Bull are looking to wrap up second place in the constructors' championship this weekend and Ferrari's ninth and 10th in FP1 will have given them cause for optimism.
Hamilton was almost four tenths slower in the second session but finished with the quickest time nonetheless, with Rosberg this time finishing in second.
Williams were the standout performers, though, with Valtteri Bottas and Felipe Massa - contesting his last Grand Prix on home soil before retirement - finishing third and fourth respectively.
Ricciardo and Verstappen were in close pursuit of the Williams pair, ahead of Sebastian Vettel, Kimi Raikkonen, Nico Hulkenberg and Jenson Button.
The highlight of the session came after Fernando Alonso, who entertained viewers with his sunbathing antics during qualifying for last year's race, was forced to abandon FP2 due to an engine problem.
The Spaniard eventually found a similar camping chair from which to catch the action and was even placed in control of a camera by a trackside operator.