Daniel Ricciardo.

Daniel Ricciardo. Photo: Getty Images

Mark Webber's future at Red Bull is in doubt and judging by comments coming from the team over the weekend, fellow Australian Daniel Ricciardo may be in the box seat to replace him next season.

Team boss Christian Horner has repeated his assertion that 36-year-old Webber is ''in the autumn of his career and no longer in the spring'', while team adviser Helmet Marko has talked up Ricciardo's efforts this season.

''It is impossible now to say who will be driving alongside Sebastian [Vettel] next year. It's clear every driver would at the moment like to be sitting in a Red Bull,'' Horner said.

Webber is contracted until the end of the 2013 season. Red Bull will decide at the end of the European summer on its 2014 driver team.

There has been speculation that Kimi Raikkonen may move from Lotus to take over from Webber. But 23-year-old Ricciardo received encouraging support from Marko, who said he was outperforming Toro Rosso teammate Jean-Eric Vergne.

''In general we are happy with both drivers,'' Marko said. ''Ricciardo is currently the better one.''

Ricciardo finished 10th for Toro Rosso in Sunday's Spanish Grand Prix, won by Fernando Alonso, his second points-scoring race in three rounds. It followed his impressive seventh place in last month's Chinese Grand Prix.

Ricciardo is determined to improve his importance as he aims to step up from the Red Bull sister team, saying consistency is the key.

''The seventh in Shanghai definitely didn't hurt me but I know that I need to do more if I want to have a good chance of getting the place at Red Bull,'' Ricciardo said. ''I have to show that it wasn't just a flash in the pan.''

Relations between Webber and Red Bull number one driver Vettel remain tense after the 25-year-old German won the Malaysian Grand Prix by ignoring team orders not to overtake his teammate.

Webber's fifth placing in the Spanish Grand prix leaves him sixth in the drivers' standings on 42 points, trailing title leader Vettel by 47 points.

The point for 10th moves Ricciardo up to 12th in the standings, six points and three positions ahead of teammate Vergne.

Alonso thrilled his compatriots in a 95,000-strong flag-waving home crowd that roared in delight after he had crossed the line to grab his second win at his home race and third on Spanish soil in recent years.

AAP, AFP