Prema Powerteam has stated that an illegal part thought to have been developed by the Williams Formula 1 team did not enhance Lance Stroll's speed in qualifying for the Formula 3 European Championship at Zandvoort.
Williams protege Stroll was excluded after second qualifying because his front suspension did not conform to the regulations, meaning he loses pole position for races two and three and will start from the rear of the grid.
Prema boss Rene Rosin would not comment on speculation that the suspension modification - which was fitted only to Stroll's car - came from Williams, although reliable sources have told Autosport that Prema has had a development car at the F1 factory and there has been a Williams staff member on site at Zandvoort.
Rosin told Autosport: "Lance did not do the pole positions because of this part.
"A mistake by the team has [probably] cost him a lot of points and that's the thing that makes me sad and upset."
Stroll added: "Losing pole position for races two and three is extremely frustrating and disappointing.
"Prema put a new front suspension component on my car for the very first time today and it's now apparent [the team] made a mistake when measuring it.
"What makes it even more aggravating is that when comparing the performances of my team-mates Nick [Cassidy] and Maxi [Gunther], it's evident there was absolutely no performance gain whatsoever, so I clearly achieved my two 'poles' without any benefit from this new part."
Meanwhile, Motopark-run Red Bull junior Sergio Sette Camara's exclusion from the same session, which prevented him from moving up to pole for race three after Stroll's penalty, is believed to most likely be due to damage caused to the airbox by debris.