Adrian Quaife-Hobbs prevented former Formula 1 driver Antonio Pizzonia from making a perfect Auto GP World Series debut in practice for the championship's maiden visit to Brazil at Curitiba.
Super Nova racer Quaife-Hobbs recorded a time of 1m12.767s on his final run of opening free practice to demote Pizzonia to second place.
The Briton needs to finish within four points of rival Pal Varhaug in Curitiba's first Auto GP race on Saturday to lift the title, and is aiming to claim the crown with a strong result at this penultimate meeting of the season.
Pizzonia's second spot was secured thanks to a best lap of 1m13.303s posted just before Giuseppe Cipriani caused the session to be red-flagged with four minutes remaining.
"I have looked at a few Auto GP videos from this year and the racing looks good," said Pizzonia, who is competing in this year's Brazilian Stock Car series. "I did my seat-fitting with Ombra yesterday, but it is the first time I have raced at Curitiba in a single-seater.
"It will be hard for me having been out of single-seaters for so long, I realise I have just two half hour sessions before qualifying, which is nothing."
Valencia winner Sergey Sirotkin took third, 0.295s behind Pizzonia. The Russian, who competed in the Moscow Formula Renault 3.5 meeting last week, has a new team-mate at Euronova for this round. Italian Formula 3 champion Sergio Campana has moved across from MLR71, which is reduced to a single car for Michele la Rosa.
Quaife-Hobbs' title rival Varhaug was fourth for Virtuosi UK.
Kiwi Chris van der Drift was fifth, separated from his Manor MP Motorsport team-mate Daniel de Jong by Campana.
Van der Drift was one of several drivers to express reservations over the installation of a temporary chicane ahead of the final corner. The chicane will only be used for Auto GP and will be removed for the World Touring Car Championship.
"It is a little bit stupid, even if they decide to widen it," said van der Drift, "I think it is almost guaranteed that someone will hit it during the weekend and move it a hundred yards down the road."
In other changes to the Auto GP entry list for Curitiba, Japanese Formula 3 racer Rafael Suzuki completes an all-Brazilian line-up with Pizzonia at Ombra. Suzuki has experience of the team from F3.
Super Nova joins MLR71 in concentrating on a single car, as Victor Guerin elected to continue his relationship with Ocean Racing Technology at the clashing GP2 meeting at Hockenheim. Zele Racing will sit out the trip to Brazil, while Facu Regalia is also an absentee, leaving Campos Racing to field two cars for Cipriani and Max Snegirev.
Pos Driver Team Time Gap 1. Adrian Quaife-Hobbs Super Nova 1m12.767s 2. Antonio Pizzonia Ombra 1m13.303s + 0.536s 3. Sergey Sirotkin Euronova 1m13.598s + 0.831s 4. Pal Varhaug Virtuosi UK 1m13.667s + 0.900s 5. Chris van der Drift Manor MP 1m13.667s + 0.900s 6. Sergio Campana Euronova 1m13.779s + 1.012s 7. Daniel de Jong Manor MP 1m13.798s + 1.031s 8. Maxim Snegirev Campos 1m14.556s + 1.789s 9. Rafael Suzuki Ombra 1m15.562s + 2.795s 10. Giuseppe Cipriani Campos 1m15.579s + 2.812s 11. Francesco Dracone Virtuosi UK 1m16.079s + 3.312s 12. Michele la Rosa MLR71 1m18.779s + 6.012s