Feb.29 (GMM) Keke Rosberg has joined a growing chorus who predict that Lewis Hamilton's second season in formula one in 2008 could be much more difficult than the first.



Hamilton, now 23, earned widespread acclaim as he won four races for McLaren in 2007 and only narrowly missed making history as the sport's first rookie world champion.



But Rosberg, the 1982 world champion, reckons last year was the young Briton's F1 "honeymoon".



"Only now will his normal life (in F1) begin," the Finn, whose German born son Nico races for Toyota-powered Williams, told the magazine Auto Motor und Sport.



Rosberg said of Hamilton, who in the departure of Fernando Alonso becomes McLaren's de-facto number one: "The expectations of him now are incredibly high. He has big boots to fill.



"There will be highs and lows, and he has to get used to that," said Keke Rosberg, who in 2008 will travel to all the grands prix as a commentator for German TV.



Although he will be on-site for all the races this year, though, Rosberg ruled out assuming an Anthony Hamilton-like grip on his own son's career.



"Nico would rather talk to me about the weather than about motor racing," he laughed.



For the sake of Nico's career, he also promises to tone down his criticisms in 2008, after calling Michael Schumacher a 'Drecksack' - a rude German-language insult - a couple of years ago.



"My words harmed Nico," Rosberg admitted to the German newspaper Bild, "so I will be a little calmer in the future."