Verstappen says failure to finish Australian GP 'unacceptable'

A frustrated world champion Max Verstappen said it was "unacceptable" that he was not able to finish the Australian Grand Prix on Sunday after his Red Bull broke down when he looked destined for second.

It was the second time in the opening three races of the season that the Dutchman had failed to go the distance, after also retiring in Bahrain.

"We are so far behind (Ferrari). We need to finish races," Verstappen said after pulling over on lap 39 of 58 at Albert Park when running second to winner Charles Leclerc's Ferrari.

"I smell some weird fluid" Verstappen reported over team radio before stopping the car, jumping out and grabbing a fire extinguisher to help marshals to put out flames.

"Today was a bad day, I was managing the tyres, I could not fight Charles," he added.

"It was an easy P2 but we didn't even finish the race -- frustrating and unacceptable. These kind of things, if you want to fight for the title, are unacceptable."

Verstappen has not been happy all weekend, complaining after qualifying second about the balance of his car.

"I never felt comfortable for one lap except the long runs," he said.

The 24-year-old also moaned after organisers cut the number of drag reduction system (DRS) zones to three from four for safety reasons.

DRS allows drivers within one second of the car in front to open a flap mounted on the rear wing to increase top speed and aid overtaking.

Red Bull are considered quicker on the straight than the Ferrari, so more DRS zones would have favoured them.

Team principal Christian Horner said he could understand Verstappen's discontent.

"It's totally understandable, his frustration," he told reporters. "That was a really disappointing result not to finish the race.

"We don't know what the issue is yet, I don't think it was actually engine-related, I think it might be a fuel issue, but we need to get the car back, we need to look at what's exactly happened."

It was not all doom and gloom for Red Bull, with Sergio Perez finishing second. However, he was more than 20 seconds behind Leclerc.