The Williams team insisted that the pace showed by Alex Albon and Logan Sargeant on Friday hadn't been planned or expected, and wasn't a case of the squad 'showing off' with artificially low fuel loads.
"It has been a better day than we were expecting," said Dave Robson, the team's head of vehicle performance. "Alex and Logan were very strong today and set fast laps in tricky conditions."
Alex Albon was an impressive third quickest behind the two Red Bulls in FP1. But what really startled everyone in the paddock was when he repeated the feat in FP2, with team mate Logan Sargeant a surprise fifth.
Williams had introduced a new aero package in Montreal which saw Albon finish seventh on a track where updates intended for high-speed corner performance had not been expected to deliver.
And at the Red Bull Ring, Albon made it through to the final top ten round of qualifying but went on to just miss out on the points by finishing the race in 11th place.
This week Albon ran a new front wing which he will keep this for the rest of the weekend, while Sargeant tried a new rear wing that the team will race later in the season.
"Obviously a very good day today," said Albon. “It was a bit surprising in some ways. I have to say unexpected, you know. We’re not playing around doing weird things, it’s just a normal day for us.
“Clearly, we crossed the line and we’re in the top three, so a bit of – in some ways – head scratching, but at the same time the car feels good. We’ve got an upgrade on the car that we’ve had for two races now.
"Looking at the timesheets you can’t not be happy," he admitted. “It’s the first time we’ve seen the package working on a quick circuit and it’s looking quite good. But we’ve got to keep ourselves grounded, it’s [about] chipping away.
Nothing had suggested the sort of sudden boost in performance seen in Silverstone on Friday, however, which meant those at Williams were as surprised as everyone else by how today's practice turned out.
"We need to go and have a look at the data and try and understand it,' Robson said. "This is the first time that we have seen the upgrade package, which we introduced in Canada, run on a circuit as demanding and varied as Silverstone.
"It enabled us to collect a lot more data than was possible in Canada and Austria and will help us understand if the development direction was correct.
"It's just the high-speed cornering performance, I think," he suggested. "We did think we'd be a little bit better here back at a high-speed circuit with the package we fitted in Canada.
"I don't think we really saw the best of it until perhaps here," he explained. "In Austria, it's so tight - such a short lap - so even if the performance is there, it's so easy to get pushed down the timesheet, make a mistake, go off.
"The performance was quite good in Austria [but] there's a lot more to getting a good result there than just pure car pace," he acknowledged, adding that the team would have to analyse overnight if it affects their plans for the weekend.
"I don't think it changes anything we do," he said. "In fact going through the data and stuff tonight is probably more important than when we have a difficult Friday.
"It's more important are really to understand why it's gone well, and make sure we don't muck it up!" he smiled, pointing out that today's dry, hot and sunny weather is unlikely to continue into rest of the weekend.
"The conditions are likely to vary over the next couple of days and we still have a lot of work to do to secure a good result. We’ll focus on the things we can influence and try to maintain the good momentum into tomorrow."
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