Hamilton was overtaken by title rival Max Verstappen on the penultimate lap, leaving the British driver 12 points adrift in the championship fight. His team Mercedes appeared to buckle under pressure during the race.
Verstappen – who started on pole position – made an error at the first corner, allowing Hamilton to inherit the lead. But a questionable strategy call by the Silver Arrows allowed competitors Red Bull to perform the undercut, pitting Verstappen early and getting him ahead of Hamilton after his own stop.
Red Bull then pitted Verstappen again for fresh medium tyres, while Mercedes kept both Hamilton and teammate Valtteri Bottas out on hards.
By the end, the pair were sitting ducks as Verstappen passed both to take his third victory of the season.
But Hamilton’s former teammate Rosberg felt he could have put up a more robust defence of his position.
“Unusual from Lewis,” Rosberg said. “Close the damn door! No?
Usually, Lewis is the best one-to-one racer and I am surprised he didn’t try. At least try. Brake late, try to keep him on the outside, so a bit soft from Lewis.
Rosberg beat Hamilton to the 2016 world championship title, only to retire just days later.
Now working as a pundit, he believes that the intensity of this season is hurting Hamilton.
The seven-time champion also took displeasure to a point highlighted by Rosberg’s colleague Paul di Resta over the Mercedes chassis change between their two drivers earlier in the weekend.
“You can see the pressure is on Mercedes” added Rosberg.
“Lewis is even blaming Paul, so even he has got into his head!
“Red Bull are now really becoming the dominant force more and more, which is putting so much pressure on Mercedes and we’re seeing that Mercedes is making mistake after mistake.
“So they need to be careful, and they need to keep it together from now on to have a chance.”
Despite losing more ground in the standings, Hamilton was relatively sanguine after finishing second and believed there wasn’t much he or the team could do to stop Verstappen.
“There were marbles on the inside so I did not want to make my tyres any worse than they already were,” he said.
“He had DRS open so if he didn’t pass me there, he would have passed me on the straight afterwards, so it was pointless to defend any harder.
“And if we had a two-stop, that could potentially have done the job but it was not the cards for us and we need to find out why.”