Lewis Hamilton set the pace in second Formula 1 practice for the Hungarian Grand Prix as Red Bull emerged as Mercedes' closest challenger.
Hamilton clocked a 1m23.949s on the soft compound tyres, 0.351 seconds clear of Daniil Kvyat with the Red Bull driver's team-mate Daniel Ricciardo 0.151s further adrift.
Nico Rosberg, in the other Mercedes, was 0.719s off the pace in fourth ahead of Ferrari's Kimi Raikkonen, who maintained his advantage over team-mate Sebastian Vettel.
Red Bull's day was tainted when Ricciardo's engine expired with 20 minutes remaining, the Australian pulling off the track at Turn 11 to bring out the red flag.
Hamilton set the early pace as the field ran the medium compound tyres and increased that advantage on his qualifying simulations on the softs before the teams turned their attention to long runs.
Carlos Sainz continued Toro Rosso's strong form so far at the Hungaroring with the sixth quickest time with team-mate Max Verstappen, who missed a chunk of the session with a technical problem, 11th.
Vettel, who had two spins (at Turn 12 and Turn 1), was seventh quickest, just over half a second slower than team-mate Raikkonen.
McLaren's hopes of a stronger weekend were boosted with Fernando Alonso finishing FP2 in eighth, 1.8s off the pace, and team-mate Jenson Button two tenths further back in 12th.
The Williams of Valtteri Bottas, who was running the team's new front wing, and Felipe Massa completed the top 10.
Lotus bounced back from a troubled first session to get more than 70 laps on the board between Pastor Maldonado and Romain Grosjean, with the duo finishing 13th and 15th overall.
The team's tyres were late arriving for first practice, in what is understood to be a consequence of a late payment, and as a result it lost track time while they waited for the tyres to get into their working range.
Sauber's team principal Monisha Kaltenborn conceded on Thursday that it would be a tough weekend for her team and it proved to be the case with Felipe Nasr 14th and Marcus Ericsson 16th.
Roberto Merhi ended up 17th quickest, just 0.002s ahead of Manor team-mate Will Stevens.
Force India chose to sit out the session as a precaution while the team continued to investigate an apparent suspension problem that caused Sergio Perez's crash in first practice.
|2||Daniil Kvyat||Red Bull/Renault||0.351s||29|
|3||Daniel Ricciardo||Red Bull/Renault||0.502s||16|
|6||Carlos Sainz Jr.||Toro Rosso/Renault||1.650s||37|
|11||Max Verstappen||Toro Rosso/Renault||1.986s||19|