What happened: Lando Norris said after Friday practice in Austin that extracting lap time from the MCL40 requires near-impossible perfection, following a session in which he locked his rears and oversteered at Turn 15. McLaren debuted its final 2026 experimental floor package at Circuit of the Americas while Charles Leclerc topped both FP1 and FP2.

Why it matters: The late-season slump follows a troubled opening to the campaign, after Norris warned in June that McLaren sat three months behind in the development fight. With 17 rounds complete, the team's Constructors' battle with Red Bull has tightened while Kimi Antonelli can clinch the Drivers' title in Austin by outscoring teammate George Russell.

What to watch: McLaren will evaluate overnight setup adjustments on the updated MCL40 floor ahead of Saturday's qualifying sessions and Sunday's United States Grand Prix.