Hamilton's one-stop bid for victory at the Paul Ricard Circuit fell short against two-stopping Verstappen as the Red Bull hunted down the seven-time F1 champion before making the race-winning pass on the penultimate lap of 53.
In his role as a Sky Sports F1 analyst, Rosberg felt Hamilton had allowed Verstappen to pass far too easily even though the Briton had been on a set of hard tyres for 34 laps compared to the 19 of Verstappen on the medium compound.
"[It was] unusual from Lewis," remarked Rosberg. "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 somehow.”
Asked to respond to Rosberg's claims, Hamilton said: "Firstly, there are marbles on the inside, so I didn’t want to make my tyres any worse than they already were.
"He had the DRS open, so if he didn’t pass me there, he would have passed me on the straight afterwards, so it would have made zero difference and I just had no front end, so he would have got me either way.
"It was pointless to defend any harder. You saw what happened to Valtteri [Bottas] - just ended up going straight on - so, there was no point messing up the tyres anymore."
After Bottas had pitted after 17 laps, Mercedes had also waited for two laps before calling in Hamilton, allowing Verstappen to perform the undercut following his first stop after 18 laps.
Assessing his team's strategic errors, Hamilton said: "If we look, with hindsight, for sure if we had stopped earlier before they had stopped, come out ahead, and just gone onto a two-stop, probably could have won the race but it would have still been very difficult.
"Their pace was generally very, very strong. I was able to keep them at bay when he was behind me but if he [Verstappen] had not made a mistake in turn one, they would have just led the race all the way, probably."
As to whether a two-stop plan would have been worth trying, Hamilton added: "Two-stop, probably… two-stop would potentially have done the job.
"But it was not on the cards at all for us, so we’ll do some analysis and try to figure out why."
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