MELBOURNE (AFP) - Red Bull were left puzzling over an engine software problem which left Formula One world champion Sebastian Vettel struggling in qualifying on Saturday and endangered his bid for a record 10th consecutive win.
The German missed out on the top 10 starting grid positions for the first time since Abu Dhabi in 2012 as Lewis Hamilton claimed the pole for Mercedes in Sunday's Australian season opener.
The problem with the software related to his Red Bull's Renault engine badly affected the car's performance in what were difficult, wet conditions at Melbourne's Albert Park.
And Vettel's attempt to reach the final stage of qualifying was hit when Ferrari's Kimi Raikkonen went off in Q2, meaning the cars behind him were ordered to slow down.
It was a significant setback for Vettel after Red Bull appeared to have overcome serious mechanical issues in pre-season with an encouraging first day of practice on Friday.
Vettel is searching for a fifth straight world title and a record 10 wins in a row but instead it was his new team-mate Daniel Ricciardo who will start from the front row Sunday.
"I think we have made a big step forward with the car, but of course I'm not happy that we didn't make it to Q3," Vettel said.
"I think the car is quick, but we struggled this afternoon with driveability which, in these (wet) conditions, made it even worse.
"The car seems good and Daniel did a very good job to be on the front row, so congratulations to him." He added: "It's going to be a long race tomorrow and reliability will be the most important thing to make it to the flag, but I think there will be lots of opportunities for us."
Team principal Christian Horner said: "It was unlucky for Seb. His engine software meant he was down on power with extremely poor driveability and we need to understand that, as it compromised his qualifying."