With McLaren's preparations for the 2017 F1 season badly dented by an unreliable and underperforming Honda power unit, both drivers have been vented their frustrations but Alonso has gone as far as to say Honda 'is the only problem' which is holding the team back.
Boullier, who has been reported stating McLaren would win with Mercedes engines, says managing an experienced former F1 world champion in Alonso and his young team-mate Vandoorne has required different approaches to keep both drivers happy.
“With both drivers obviously you have to react differently,” Boullier said. “Stoffel is fresh, young and motivated as ever, so even if he's disappointed because he doesn't have the car to perform well - and I say if - then he will recover and it's something to learn.
“In the case of Fernando he has got more experience and he wants a competitive car, so he also knows - and this is something I keep saying - but since day one he knows the project, he knows everything, he knows how it goes and how it develops and where we go.
"His patience is based on his own expectations but he has a full view of what is going on.”
7 times the F1 season started with a bang!
Reports emerged this week of McLaren sounding out the possibility of switching to customer Mercedes engines as the crack begin to form in its partnership with Honda having signed with the Japanese manufacturer in 2015.
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