Jun.9 (GMM/Inautonews.com) Red Bull does not see the light at the end of the tunnel yet, Dr Helmut Marko has warned.

The former champions had a particularly bad weekend on Montreal’s long straights, but also notable was the dwindling smile on the face of Daniel Ricciardo.

“Daniel struggled for pace all weekend,” said team boss Christian Horner, “which is unusual for him.”

It revved up speculation the normally-grinning Australian is positioning himself on the driver market, as most of his comments in Montreal indicated a steady loss of patience with leading the charge for Red Bull.

“I think his comments were just a bit of frustration,” argued Horner, “especially after winning here last year and this time he was beaten by his teammate.”

Indeed, Horner took issue with Ricciardo’s claim that, amid Renault’s well-documented engine troubles, development of the chassis has also stalled.

“We have moved forwards with the chassis,” Horner insists, “and we’ve seen that since the second race in Malaysia.

“The good thing is that we can bring updates for the car every two weeks,” he added, “while improving the engine takes much longer.”

The next race is an important one for Red Bull, as it is taking place in Austria at the ‘Red Bull Ring'; a race promoted by team owner Dietrich Mateschitz.

But Dr Marko told APA news agency: “Spielberg will be even more difficult for us.

“The circuit is all about accelerating out of tight corners into quite long straights, which in our current engine situation is the worst thing possible.”