Norris Edges Out Oscar Piastri in Sao Paulo Practice Session
The British driver has beaten his teammate at each of the past five race weekends.
The McLaren driver just pipped team-mate and championship contender the Australian for the top spot in the closing stages of the practice session at the Brazilian Grand Prix.
Norris, who seized the points lead from his teammate by a single point after taking the win in Mexico City a fortnight back, beat the Australian by 0.023 seconds.
Before then, Piastri had been the quickest of the McLaren pair throughout the hour before sprint qualifying scheduled for 6:30 PM GMT.
Max Verstappen, the other racer in realistic title contention, trailing 36 points behind Norris, finished in 17th place as his Red Bull team opted for a different programme.
His teammate the Japanese driver was the sole competitor to go off, though minor, when he rotated at corner four during the early running.
Tsunoda lost control over the curbs on exit before sliding over the escape zone, and was lucky to escape with just a minor contact of the fence.
The Ferrari of Lewis Hamilton also lost it, at the conclusion of the practice, turning around through the quick descending Mergulho corner leading to the final corner on to the pit straight.
Hamilton finished practice in P19, just behind teammate Charles Leclerc.
The McLaren pair were far ahead of the remaining drivers, with the German's Sauber in third, 0.619 seconds slower than Piastri's best.
The Aston Martin of the Spanish driver was in fourth, with the Sauber of Gabriel Bortoleto fifth from the Mercedes of George Russell and Alpine's Gasly and Williams' Carlos Sainz.