Hamilton slowed by undertray issues during the race!
The Mercedes mechanics have apparently found the cause of Lewis Hamilton's lack of pace during the Australian Grand Prix: damage to the floor of the W10!

Surprisingly slow in the race, Lewis Hamilton actually raced with a handicap. Shortly after the finish, his team tweeted this message: “We found damage under Lewis’s floor, near the left rear tire.” Part of the floor was indeed torn off during the Grand Prix!
Shock on debris or a curb, the origin of this damage remains unknown, but it already explains the lack of balance complained about by the five-time world champion upon arrival, who is “unhappy” with the situation.
The question to resolve is whether this problem occurred from the first relay, ended by a tire change made in the sixteenth lap, to protect the second place against Vettel, who came in a lap earlier.
It was at this moment that Hamilton’s lack of pace began to be noticed, as he was running slower than Valtteri Bottas, who was faster on worn tires. Nevertheless, driver #44 was never able to catch up with driver #77, with the former managing his lead over a rather persistent Verstappen. And the missing piece of the floor also disadvantaged Hamilton in the battle for the fastest lap, eventually won by Bottas. But Hamilton contributed to Mercedes’ first one-two finish in Australia since 2016. At the time, his former garage neighbor Nico Rosberg won the race, before becoming world champion eight months later.
✊ The wins you don’t expect are the best kind! #DrivenByEachOther pic.twitter.com/q3sZjBsNld
— Mercedes-AMG F1 (@MercedesAMGF1) March 17, 2019