Daniel Ricciardo admits it will be no easy task to fend off Nico Hulkenberg's challenge in 2019.
There has been much fanfare about Ricciardo's move from Red Bull, but the Australian's Renault teammate Nico Hulkenberg looks better so far in Melbourne.
"His long run was much better than mine," Ricciardo admitted after Friday.
"Nico is what I expected. He is fast. So I need to try to push the right-hand pedal down a bit harder."
German Hulkenberg, though, said he expects Ricciardo to speed up.
"When you change teams, you need some time," he said. "It's quite normal if the shoe doesn't quite fit yet."
Germany's Auto Bild claims Hulkenberg, 31, could be in the running to replace Valtteri Bottas at Mercedes for 2020.
It is widely expected that Esteban Ocon is the frontrunner, but German Hulkenberg's contract at Renault is also expiring.
Hulkenberg said: "When Nico (Rosberg) stopped, there was a small spark (with Mercedes), but it didn't really start a fire and I signed with Renault."
