Sepang: Norris improves late in the long run, a signal from McLaren
The drivers who start strong are not the ones who finish strong: Friday's lap times show how the pace changes, not why.
Sepang's Friday had one topic above all: tyre degradation, which Fred Vasseur, Pirelli and the drivers put ahead of any lap time.
Lap times on their own measure something simpler: how the pace changes over a long run. They mix the tyre wearing, the fuel load coming down, the track changing and the pace the driver chooses. The lap times cannot pull those apart. What follows is how the lap times moved, not how much the tyre degraded.
On the soft-tyre long runs in second practice, Charles Leclerc's lap time tends to rise by 0.19s a lap, Lewis Hamilton's by 0.29s and Kimi Antonelli's by 0.30s. For George Russell, on the longest run among the front-runners, the trend is +0.11s.
Among the soft-tyre long runs analysed, Lando Norris is the only one with a minus sign: −0.06s a lap. That does not mean every lap was quicker than the one before: it is the trend estimated over the whole run, an improvement of about six hundredths a lap. Oscar Piastri, in the other McLaren, stays almost flat at +0.01s.
The drivers' impressions of race pace do not agree. Russell pointed to McLaren as the quickest on the long runs; Antonelli sees the Red Bulls ahead, over a single lap and on race pace alike, and for Leclerc it is Red Bull that stands out. The lap times cannot arbitrate between these impressions, but they do show that the order at the start of the long runs is not the order at the end.
The timesheet is of little help. Leclerc topped second practice with a 1:37.528, eight thousandths slower than the 1:37.520 that had put Verstappen on top in first practice. But Verstappen never fitted the soft in second practice: the plan, Verstappen explained, was a long run in case the rain came.
Over a single lap on the soft, neither Mercedes has a valid time. The team said neither driver made the most of their only push lap on that tyre, and the stewards deleted Antonelli's time for track limits at the penultimate corner. Both set their best times on the medium.
To see where the order changes, we split the laps of those long runs by tyre age: on one side those with fewer than eleven laps on the tyre, on the other those with more than eleven. Eleven is the median age of the whole sample, not the halfway point of each stint nor a point where something gives way. Laps run at exactly eleven are left out, and the parts are short: two to eight laps per driver.
Before the eleventh lap on the tyre Norris was the slowest of the Ferrari, Mercedes and McLaren drivers: a median of 1:45.083 over five laps, against 1:44.540 for Leclerc and 1:44.617 for Russell. Antonelli was quicker still in that part, but his sample contains no laps beyond the threshold, so there is no second part to compare.
After the eleventh lap the order changes. Norris came down to 1:44.783 over three laps, while Leclerc rose to 1:45.449 and Russell to 1:45.743. Among the drivers in the soft-tyre long runs with laps both before and after the threshold, Norris is the only one whose median improves.
The signal comes from only one of the two McLarens. Piastri does not follow the same pattern, going from a median of 1:44.883 over two laps to 1:45.140 over four. In these data the change in order belongs to Norris, not to both cars.
The chart shows Leclerc's and Norris's laps along the run: the two lines cross between the eleventh and the twelfth lap on the tyre.
What produces Norris's line, these laps cannot say: a car that is gentler on its tyres, a driver who holds back early so the tyres last, and a fuel tank emptying can all draw the same curve. The drivers don't settle it either: Norris said the team is struggling more than it would like, and Piastri puts McLaren a small step behind Red Bull, Mercedes and Ferrari.
Mercedes, who said they had looked unusually off the pace over a long run, are level with Ferrari in the first part and lose ground in the second; Russell blames tyre overheating rather than the upgrade. Red Bull stay out of this comparison, having done their long run on the medium: on that compound Verstappen's trend is +0.16s a lap, a number that cannot be set beside the soft-tyre ones.
On Sunday the same measurement can be repeated on the first stint, with race fuel and race tyres. There it will show whether Norris's Friday pattern holds.