Eric Boullier is convinced McLaren would be challenging for Formula One race wins were they still powered by a Mercedes engine.
The British constructor ended their 19-year association with Mercedes in 2014 to link up with Honda but the results have been less than impressive.
In 2015, Fernando Alonso and Jenson Button only managed 27 points between them as McLaren finished ninth in the constructors' championship.
Last season there was a slight improvement as 76 points were accrued, however a podium finish still eluded them - in fact the last time they have finished in the top three was the 2014 Australian Grand Prix.
But Boullier believes they would be battling with Ferrari, Red Bull and the Silver Arrows if the latter was still their engine supplier, rather than Honda.
"I think so," the Frenchman told AS when asked if they would be winning with Mercedes.
"Yes, we would be winning again."
And when questioned if he had thought about seeing a McLaren with German power units, he replied: "Let's just say a few times."
McLaren's problems reared their head most days during the pre-season testing weeks in Barcelona, leaving the team massively underprepared for the 2017 season.
Some have suggested another poor year could see Alonso leave the team but Boullier is confident the Spaniard will stay with the team no matter what.
"Yes [we have talked about 2018, but it is too soon, but of course we have spoken," he added.
"He is the best driver and he needs to win, I think he can do it here and our job is to help him get it."