Mercedes racer Russell wiped out from seventh place two laps from the chequered flag in Melbourne while chasing after the Aston Martin driver. He lost the rear axle through Turn 6 to skate over the gravel, and hit the Turn 7 wall before bouncing back into the middle of the circuit.
This left the 58-lap contest to end under virtual safety car conditions as Carlos Sainz led Charles Leclerc for a Ferrari 1-2 finish in a race from which Max Verstappen retired with a dramatic right-rear brake fire.
Mercedes believed Alonso lifted off the accelerator, braked and downshifted a gear differently compared to his previous laps. This allowed Russell to close quicker than expected, possibly causing the Briton to lose control in the wake of the Aston Martin.
After a lengthy hearing with the FIA stewards, it has been determined that Alonso did alter his driving style in an "extraordinary" way to fulfil Article 33.4 of the sporting regulations.
This reads: "At no time may a car be driven unnecessarily slowly, erratically or in a manner which could be deemed potentially dangerous to other drivers or any other person."
Accordingly, Alonso was awarded a drive-through penalty, but this has been converted to a 20-second reprimand - dropping him from sixth to eighth, behind team-mate Lance Stroll and Yuki Tsunoda. He has also lost the clean record on his FIA superlicence via the addition of three penalty points.
Alonso explained that he had approached the corner differently by lifting early and carrying less speed, but this was to gain a better exit. Russell countered that the move was "erratic", caught him off-guard and the close distance robbed him of downforce at the corner apex.
The stewards' verdict read: "Telemetry shows that Alonso lifted slightly more than 100m earlier than he ever had going into that corner during the race. He also braked very slightly at a point that he did not usually brake (although the amount of brake was so slight that it was not the main reason for his car slowing) and he downshifted at a point he never usually downshifted. He then upshifted again and accelerated to the corner before lifting again to make the corner.
"Alonso explained that while his plan was to slow earlier, he got it slightly wrong and had to take extra steps to get back up to speed. Nonetheless, this manoeuvre created a considerable and unusual closing speed between the cars."
However, the stewards could not definitely conclude whether Alonso's manoeuvre was intended to cause Russell's wipe-out, nothing that the two-time F1 world champion should not be responsible for the dirty air that caused the shunt.
Their conclusion continued: "Specifically, in this case, the stewards have not considered the consequences of the crash.
"Further, the stewards considered that they do not have sufficient information to determine whether Alonso's manoeuvre was intended to cause Russell problems, or whether as he stated to the stewards that he simply was trying to get a better exit.
"Should Alonso have the right to try a different approach to the corner? – yes. Should Alonso be responsible for dirty air, that ultimately caused the incident? – no.
"However, did he choose to do something, with whatever intent, that was extraordinary – IE lifting, braking, downshifting and all the other elements of the manoeuvre – over 100m earlier than previously, and much greater than was needed to simply slow earlier for the corner? – yes…
"By his own account of the incident he did, and in the opinion of the stewards by doing these things, he drove in a manner that was at very least "potentially dangerous" given the very high-speed nature of that point of the track."
