Jun.9 (GMM) Amid the most successful period in his Formula One career to date, the frustration has often shown on Nico Rosberg's face.

As journalists dutifully asked a few sporting-related questions in Canada, SID news agency revealed that the German 'rolled his eyes' and put on a 'tortured smile' as he asked the press men: "Can we come to the tyre issue now, please?"

He was sarcastically referring to 'testgate', a scandal of typical F1 proportions that is questioning Mercedes' fairness and integrity just as Rosberg delivered a hat-trick of poles and a lights-to-flag Monaco victory.

Team director Toto Wolff, however, insists Rosberg is "not frustrated because he's too professional" and it is, after all, "a management issue".

Rosberg agreed, asking rhetorically: "How important is it, what others say or write?"

Wolff insisted Rosberg is telling the truth on that score.

"He is a disciplined thinker, blessed with great talent. He can always extract his very best performance, because he can put aside everything else and focus only on the sporting side," he said.

Wolff, meanwhile, is more open about his own frustration.

"Of course," he admitted. "For whatever reason, people are always looking for the controversy.

"Maybe that's even more unpleasant for us because we are now more competitive -- that the controversy is coming across in the media as more important than the drivers' performance."