Helmut Marko has indicated Sebastien Buemi's place at Toro Rosso may not be secure.
Red Bull's famously-brusque driver manager Marko was openly disappointed with the young Swiss after 2010, with the appointment of Daniel Ricciardo as Friday driver adding even more pressure now.
But Buemi, 22, was impressive on Saturday, out-qualifying his teammate Jaime Alguersuari and securing the Red Bull junior team's first Q3 appearance
"Sebastien has withstood the pressure and I congratulate him," Marko told Blick newspaper in Melbourne. "But now he has to confirm it in the race.
"We await that with interest," he added.
Buemi was also happy with his performance but aware that he can not relax yet. "I will push in the race like there's no tomorrow," he is quoted as
Spaniard Alguersuari is also feeling the pressure and told Spain's AS newspaper he felt "slightly uneasy" when Australian Ricciardo was in his car e
"For now, they are both treating me well," Ricciardo is quoted by O Estado de S.Paulo. "But I don't know how it going to be if I am faster than the
But Alguersuari insists Ricciardo's presence is not a problem.
"It isn't creating any discomfort," he said. "Daniel is quick but he still has a lot to learn in formula one. It's not enough to just be quick.
"My war is with Buemi, not Daniel," he added.