Former world champion Nico Rosberg believes his old teammate Lewis Hamilton “starts to lose that edge” whenever a weekend doesn’t go his way, and has warned his Formula One rivals to make hay while the sun shines as he always “comes back so damn strong”.

Reigning champion Hamilton has made by all accounts a poor start to his title defence, having failed to win one of the first three races of the season – something that Mercedes have not experienced since 2013. The 33-year-old trails championship rival Sebastian Vettel by nine points this season, although it could have been much worse had the Ferrari driver not been taken out of contention in last Sunday’s Chinese Grand Prix by Max Verstappen, and Hamilton has cut a perplexed figure in recent weeks having struggled to identify why the team are lacking pace this year.

Heading into next weekend’s Azerbaijan Grand Prix in Baku, Hamilton will hope to rediscover the pace that he showed their last season before an incident with Sebastian Vettel and a loose headrest cost him a chance of victory. However, the now-retired Rosberg believes that the likes of Vettel and his other championship rivals must make the most of Hamilton’s current issues as from his own experience, when the Briton gets it right he is nigh-on unbeatable.

“When it doesn’t go perfectly, he starts to lose that edge a little bit and a touch of motivation or whatever and then just struggles for a while,” Rosberg said on his YouTube channel.

“And those are the races you have to maximise…because Lewis always comes back, and when he comes back he comes back so damn strong that he’s almost unbeatable. And so let’s see when that happens.”

Rosberg’s once frosty relationship with Hamilton has very much thawed since the German announced his surprise retirement just days after winning the 2016 world championship, which saw him take full advantage of Hamilton’s slow start to the season after he tailed off towards the end of the previous year. Rosberg won the last three races of the season and took that momentum into 2016 to claim the first four grand prix of the year, but after Max Verstappen won the Spanish Grand Prix following the famous first-lap crash between the Mercedes teammates, Hamilton went on to win six of the following seven races.

But with the Mercedes evidently lacking outright pace compared to the Ferrari across the last two races, Hamilton is fully aware that the team have plenty of work to do heading to Baku.

“Obviously it’s a tough battle ahead of us,” he said. “I would say on my side but also us as a team, we’ve been underperforming.

“I have got to try and rectify that and get myself back into normal performance mode, otherwise more valuable points will be lost.”

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