The 2016 world champion has said his former teammate is struggling to find his form in 2018. The championship battle looks to be much closer than in recent seasons and Mercedes along with
Lewis Hamilton, haven't hit their stride yet.
Nico Rosberg has claimed his former teammate's struggles are down to a lack of form.
Lewis Hamilton is second in the world championship just nine points off of leader Sebastian Vettel, however, he hasn't been anywhere near top form since the first round in Australia.
Rosberg said that he has seen this all before and is familiar with this sort of phase from Hamilton, which in turn can lead to "mistakes".
"Lewis is not in form but he's always had such phases," Rosberg told RTL television.
"If he's not confident, he starts to think and he makes mistakes.
"I'm curious to see if he comes back in Baku."
Baku is one of the only circuits currently on the F1 calendar that Hamilton has not recorded a race win at, he will need to remedy this to recover from a tough beginning to his title defence.