Formula One drivers Fernando Alonso and Valtteri Bottas were given the all-clear on Thursday to race in the Malaysian Grand Prix this weekend after missing the season’s start because of injury.

F1 medics cleared two-time world champion Alonso to make his McLaren debut after he suffered a concussion in a still-unexplained crash in testing on February 22.

Alonso, who suffered temporary memory loss in the crash, was sidelined for the season-opener in Australia to avoid the risk of a second head impact too soon after the first.

The Spaniard “passed all mandatory fitness tests and has thus been declared fit to race in this weekend’s Malaysian Grand Prix”, governing body FIA said in a statement.

Williams driver Bottas was also passed fit at the Sepang circuit after missing the season’s first race on March 15 with a lower back injury.

Alonso’s MP4-30 car will carry an extra sensor in Malaysia after he recalled “heavy steering” before his crash on an innocuous stretch of Barcelona’s Circuit de Catalunya.

Several observers commented that the crash seemed unusual, with Alonso’s manager Flavio Briatore labelling it “very strange”.