SAKHIR, Bahrain — Ferrari driver Charles Leclerc clocked the fastest time ahead of Mercedes driver George Russell in the first session of Saturday’s third and final day of Formula One testing.

Leclerc completed 67 laps and was .42 seconds quicker on soft tires than Russell, who did 83 laps on mediums. Seven-time F1 champion Lewis Hamilton will replace Russell in the W14 for the afternoon run.

With Lance Stroll still sidelined because of a wrist injury sustained in a bicycle accident, Aston Martin again used F2 champion Felipe Drugovich and he was third fastest — about 1 second behind Leclerc.

It is unsure whether Stroll will recover in time to race next weekend in the season-opener in Bahrain, and teammate Fernando Alonso offered no indication.

“No news,” the two-time F1 champion said. “It’s a private matter so I have nothing to comment.”

Sergio Perez took over from two-time defending world champion Max Verstappen at Red Bull and was fourth quickest on mediums.

There was a brief red flag at the start after some debris was cleared off the track, seemingly from Perez’s RB19.

A second red flag came out later when Valtteri Bottas parked his Alfa Romeo in a run-off area.

Verstappen was fastest on Thursday and Zhou Guanyu topped day two of testing Friday.

Times set in testing offer a rough guide to a team’s true speed for the season, with the cars often set up in very different ways.

But McLaren CEO Zak Brown said Friday he felt his team was behind its projected targets.

Brown will hardly have been reassured when Australian driver Oscar Piastri had a big spin on the track, although he recovered quickly.