Mercedes team principal Ross Brawn has conceded the team could struggle with the 'new' Pirelli tyres in Belgium later this month.
Lewis Hamilton gave the squad its third victory of the season at the Hungaroring just prior to F1's summer break, but despite that success, Brawn remains cautious.
Indeed he has said the situation with the tyres is a 'strong moving target' and the fact the event at Spa-Francorchamps will only be the second with the revised rubber, which combines the 2012 construction with the 2013 compounds, will only complicate matters.
“We've had three specs of tyre this year - what we began the season with, what we took to the Nurburgring and what we had in Hungary,” he told The Press Association
. “So you have to keep track and there's no doubt that it will suit people more than others.
“Quite frankly, I still don't have any idea whether this tyre is the one that suits us more or less than anyone else.
“It's certainly changed the order a little because some teams who were doing exceptionally well, like Force India, struggled with it. I'm sure they will come to terms with it, but it clearly behaves differently.
“We'd just started to understand the original tyre at Silverstone when we had to change it again.
“There are slopes that people will be running along in terms of their understanding of the tyre.
“We got it on the button in Hungary, but it doesn't mean we'll get it right at Spa because every situation is different.
“You just build up your understanding of it to use it properly.”