One of Formula 1's most experienced drivers has urged his team to address a problem which he believes hampered his chances at the Canadian Grand Prix.
The Montreal event was one of the most entertaining races of the year, as heavy rain caused havoc for drivers as they battled to keep their cars on the track.
Five vehicles failed to finish Sunday's showpiece, including both Ferraris and the Red Bull of Mexican star Carlos Perez.
Defending champion Max Verstappen got back to winning ways after a disappointing weekend in Monaco last time out, capitalising on a timely safety car to edge ahead of Lando Norris.
It was the Dutchman's sixth victory of the season - his 60th overall in F1 - as he extended his lead over Charles Leclerc at the top of the drivers' standings.
German laments 'missed opportunity'
In a thrilling opening period, Haas' gamble to start the race on wet tyres looked to have paid off handsomely, as Kevin Magnussen and Nico Hulkenberg flew through the field unchallenged to break into the top 10.
Their progress was eventually halted, however, as teams got to grips with the testing conditions, with both drivers finishing in the bottom half at the end of a frustrating afternoon.
Hulkenberg - who will join Sauber next season - lamented the performance of his car post-race, admitting an opportunity had been missed to score significant points.
With attention now turning to this weekend's race in Barcelona, the German called on the team to carry out an investigation into why his car was 'not fully healthy'.
"The missed opportunity was [Saturday] and generally all weekend,” Hulkenberg said, as reported by The Daily Express. "The problem we've had on my car [is] that somehow it's not fully healthy, I think, on the aero side or somewhere.
"I still feel after the race that I have a problem with it, that is not fully at 100 per cent where we're supposed to be. But you know, obviously, you do what you can with what you have.
"The whole weekend, especially on my side of the garage, and from lap one, I didn't feel right and happy with the car and we need to investigate what was going on because that really compromised our weekend."