The Undercut

In Formula 1, track position is everything and overtaking on track is hard. The undercut is the most common way teams win a place in the pit lane instead of on the circuit. The idea is simple: fresh tyres are fast tyres. A new set of softs or mediums can be one to two seconds a lap quicker than a set that's twenty laps old, and that difference is at its largest in the first few laps before the rubber wears in.

Here's how it plays out. Two cars are running nose-to-tail, the leader controlling the pace. The chasing team pits first. On fresh tyres, that driver immediately bangs in a string of fast laps — these are the "undercut laps." Meanwhile the leader is still circulating on tired tyres, losing time hand over fist. When the leader finally pits a lap or two later, they rejoin behind the car that stopped early. The position has changed without a wheel-to-wheel move.

The undercut isn't free, though, and it doesn't always work. It depends on a few things lining up. The out-lap matters enormously: the driver who pitted early has to get heat into cold tyres immediately and not lose the time they just gained. Traffic can ruin it — rejoining among slower cars erases the advantage. And the tyres have to actually offer that early pace; on circuits where new tyres take a lap or two to switch on, the undercut is weak and the overcut (staying out longer on old tyres while the rival struggles on cold new ones) can work better instead.

Strategists weigh all of this in real time. They watch the gap, the tyre age, the pit-lane loss time at that circuit, and where traffic will be. A successful undercut often decides the race — many Grand Prix "overtakes" you remember actually happened in the pit lane, several laps before the cars swapped places on track.

Open the Strategy view and compare two drivers' stints side by side — when one driver's pit stop lands a lap or two before the other's and they come out ahead, you're looking at an undercut.