Three weeks after the Miami upgrade bonanza, the 2026 Formula 1 season is poised for a new twist as Mercedes and McLaren both bring substantial upgrades to the Canadian Grand Prix.

Mercedes has been the dominant force in the early 2026 rules era, sweeping the first four races from pole. Sophomore driver Kimi Antonelli heads to Canada as the championship leader after securing a hat-trick of grand prix wins in Miami, leading team-mate George Russell by 20 points.

Despite Mercedes' continued dominance, the competition has been gradually reducing the deficit. Ferrari initially looked like the strongest challenger, but McLaren has surged in recent weeks as it got on top of its Mercedes power unit. Both teams brought large upgrade packages to Miami, which seemed to have a bigger impact on McLaren than on Ferrari.

McLaren’s Miami form was somewhat deceptive. Lando Norris beat Antonelli to sprint pole on Friday before he and team-mate Oscar Piastri went on to record a 1-2 win in Saturday’s 19-lap sprint. However, Mercedes still proved to be the best car across grand prix qualifying and the race.

Why Canada Will Be the Next Battleground for Early 2026 Car Upgrades

Mercedes has consciously kept its package back for the Circuit Gilles Villeneuve round this week, hoping to restore a more comfortable lead. If Miami's regression was calculated, Antonelli still winning the race could be seen as an ominous sign of things to come.

McLaren isn't done yet either, having decided to split its upgrades across Miami and Montreal. Motorsport.com understands the Woking squad deployed around 60% of its upgrades in Florida with another 40% coming this week, centered around a new front wing. Given the importance of a front wing on the entire aero performance, it could still be a powerful weapon as McLaren aims to improve its aerodynamic efficiency, particularly on Montreal’s many straights.

Mercedes’ struggles in correlating upgrades have made its F1 chief Toto Wolff somewhat cautious. "Yes, something is coming, or rather the bigger update will come in Canada," he said. "Now we have to make sure it actually works. On paper it’s easy to say you’re three or four tenths faster. But it has to show on track and on the stopwatch."