Toro Rosso driver Jean-Eric Vergne has admitted that his team face "major problems" in trying to get their cars ready for the start of the Formula 1 season.
On the final day of testing in Bahrain, which saw Mercedes Nico Rosberg top the timesheets, Vergne was only able to complete 19 laps and, while the Frenchman admits to being frustrated, he insists that the team must remain calm.
He told reporters: "There's no point in making negative comments, because everyone knows we are facing major problems and we are not alone in that.
"We knew when we came to Bahrain that there had not been enough time since the previous test to have solved all our issues.
"It's frustrating, but we need to keep calm and not get stressed as there are still a few weeks before Melbourne".
Toro Rosso have been one of the teams that have endured problems with their Renault engine. The issues with the power unit supplied by the French manufacturer have also blighted Red Bull, Lotus and Caterham's pre-season preparation.
