"The auto balance has been good from the first run so it has just been a case of small balance tuning to keep the vehicle in the right window as the track grip came up".
A day after Verstappen half-jokingly threatened to head-butt anyone who asked him about recent crashes, the Dutchman completed the 4.36km lap in 1 minute, 12.198 seconds. "If we can escape this weekend without it, then I'd rather take it somewhere else". Ericsson hit the wall on the exit of Turn 9 and had to return to the pits, but was lucky the incident was not more severe as a Red Bull - just off line on the exit of the corner - almost collected the Swede as he bounced off the concrete.
"Overall we've had a fairly straightforward day, the vehicle has run reliably and it was just the red flags and virtual safety cars that caused us to have to adapt the plan a little", Shovlin revealed.
It was the second time this season Verstappen has failed to finish. It was the best time in Friday afternoon's (Saturday NZ time) practice and a full second better than his best lap in the morning, when he was also the fastest.
"I'm really exhausted of all the comments about me - that I should change my approach", he said.
Although Renault have introduced an upgraded engine this weekend, Red Bull believe they are surrendering around three tenths of a second to Ferrari and Mercedes on the Montreal straights - food for thought as the team deliberate the identity of their engine providers for next season. "There was a little bit more, but I'm still happy".
Hamilton was unusually out of sorts on a track where he has excelled so many times and a series of mistakes left him struggling to keep up with his rivals. Sainz finished behind Stoffel Vandoorne in the standings; the Belgian was the other casualty of the session, breaking his rear suspension after hitting the wall through on the exit of Turn 8. The 19-year-old made it slowly back to the Williams garage.
Only Force India reserve Nicolas Latifi, in his first F1 practice session, and Hulkenberg, who did not set a time, were behind the Williams on the time sheets.
He has raced in the F2 series the last two seasons and now sits 10th in F2 standings after eight races this year, including a third-place finish at Baku, Azerbaijan.