Jonathan Wheatley has revealed the "long conversation" he had with Mattia Binotto in the days before his Audi exit was confirmed. The two of them had formed a leadership coalition at the team, with former Ferrari boss Binotto serving as head of the Audi F1 project and Wheatley as team principal.

But a major change has been made just two rounds into Audi's debut season with its name on the grid. For unspecified "personal reasons", Wheatley has stepped away from the Switzerland-based team and he has been strongly linked with a switch to Aston Martin, who are believed to have made the former Red Bull sporting director an offer.

He gave no indication of his impending departure at the Chinese Grand Prix, where he was leading Audi's trackside operations as usual. He also spoke to reporters after what proved to be his final race in charge, during which he reflected on their early-season reliability issues by naming their engines as "an area of focus" for the months ahead.

"I had a long conversation with Mattia about this, the analysis that we've done," Wheatley said. "We're careful about what we say in public about it. One of the areas of focus for us in the next development cycle is the PU. We think there's some work that we can do in that area."

Reliability problems aren't their only issues on that front, as the Audi power units found themselves wanting at times on track in Shanghai including when Nico Hulkenberg was trying to battle with other cars. However, the German found himself hampered by a lack of driveability and that cost him when going wheel-to-wheel with rivals.

Improvement on that front is more something under the purview of Binotto and his engineering background, which Wheatley alluded to as he answered questions on the topic. He explained: "It's a track that exposed our weaknesses in many areas. One of the things that was interesting here is that in racing situations, how key driveability is.

"It remains a challenge to us to get on top of these driveability issues, because basically Nico had a couple of situations, at I think turn six, where it was hard to recover from them because you've got to get the engine back in its operating window."

Asked if engine deployment seemed to be the main cause of the lack of driveability encountered, he added: "You're getting very close to Mattia-type questions and not Jonathan-type questions. But look, basically, it;s the response of the PU in those situations when you have to react rather than act, I suppose."