Red Bull team principal Christian Horner says Renault's urgency to develop its power unit has increased since it returned as a full constructor.
Poor reliability and performance from the Renault power unit led to a breakdown in the relationship with Red Bull last season, with the team seeking a new supply from elsewhere. Eventually Red Bull had to stay with Renault, with the French manufacturer also returning to F1 as a constructor having taken over Lotus.
Horner says the extra involvement from Renault this season has led to a noticeable change in attitude.
"I think they have all the opportunities," Horner told the official F1 website when asked if Renault will be able to increase its performance this year. "Over the last six months they really started to make progress. Now that they have their own team as well their determination and urgency only increased."
With Daniel Ricciardo setting the fastest lap in the Australian Grand Prix, Horner played down how much progress has been made so far but is pinning his hopes on a mid-season upgrade.
"Melbourne, of course, was a very positive race for us. Daniel raced very well and the car was competitive throughout the race. The degradation on the tyres was good and the characteristic of that circuit suited us, as there is not a huge dependency on power. The next few races will be much tougher - until we get a significant upgrade with the power unit."
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Scene at the Bahrain Grand Prix
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