Rosberg was fastest in both sessions, finishing with the best time of the day with a lap of 1 minute, 12.123 seconds at Interlagos. Hamilton was .0213 slower. Kimi Raikkonen of Ferrari was third, about half a second behind Rosberg.
The Mercedes drivers are the only two vying for the Formula One title. Hamilton leads Rosberg by 24 points with 75 available going into the last two races.
The title will not be decided in Brazil as the season-ending race in Abu Dhabi will be worth double points. Hamilton can win his second world title with consecutive second-place finishes or a third in Brazil and a second in Abu Dhabi on Nov. 23.
As they did for most of the season, the Mercedes drivers led throughout the practice sessions, which were run under dry conditions at Interlagos.
"It was a very normal day for us," Rosberg said. "There was a lot of understeer early but after we solved the problem the car was very fast, as always. I liked the result."
Hamilton doesn't think he needs to improve a lot to catch up with his teammate.
"I just need to put a lap together," he said.
The newly-resurfaced track offered little grip compared to previous years and was especially slippery in the afternoon under warmer temperatures. Several drivers span and went off the track, including Hamilton a few times.
"The track is really difficult to drive in these temperatures," he said over the team radio.
Both practices had to be briefly red flagged four times, including when Force India's Spanish test driver Daniel Juncadella crashed into a tire barrier in the first session. He was not injured.
There will be another practice on Saturday before qualifying.
Fernando Alonso of Ferrari finished seventh but had his day cut short in the second session after his engine appeared to blow up. The Spaniard had to quickly get out of the car as flames appeared to spread. The incident caused one of the red flags.
Raikkonen also went off the track several times in both sessions before managing to finish with the third-fastest time.
Home crowd favourite Felipe Massa, a two-time winner in Brazil, finished sixth, one spot behind Williams teammate Valtteri Bottas.
Red Bull, which has won four of the last five races in Brazil, struggled in the first session but picked up the pace in the second with Daniel Ricciardo finishing fourth. Sebastian Vettel, who at one point said there were "some serious" problems with his car, ended ninth.
McLaren's Jenson Button, still uncertain about his future in F1 next season, had mechanical problems and was the only driver without a timed lap in the first session. He was only 16th in the second.
There will be only 18 cars again on the grid this weekend as Marussia and Caterham continue to deal with financial problems. Marussia was shut down on Friday and Caterham launched a crowdfunding project to ease its financial difficulties and return to the grid for the final grand prix.
Hamilton is going for his sixth win in a row and 11th in the season, both of which would be a first for a British driver. Rosberg has four victories. Neither driver has won in Brazil.
Mercedes has placed 1-2 in 10 of the 17 races this year, and clinched the constructors' championship with three races to spare. It has 14 victories between the two drivers, one short of the season record shared by Ferrari and McLaren.
The 4.3-kilometre counterclockwise (2.6 mile) Interlagos track has new runoff areas and a new pit entrance and pit exit, all added to improve safety.
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