The French striker played a role in helping his country secure World Cup glory at this summer’s tournament in Russia and he has since reported back to Chelsea FC to begin work under new boss Sarri.
Giroud has been limited to a substitute role in recent weeks and he has only made three appearances from the bench for Sarri’s side in the Premier League so far this term.
However, the 31-year-old is one of the Premier League’s most established strikers and Rudiger feels that he and Alvaro Morata will play a key role for the Blues under Sarri this term.
Speaking in an interview with the Daily Mail, Rudiger said: “I like him [Giroud] as a striker, he is tough and loves to use his body.
“Alvaro (Morata) trained the whole pre-season when Giroud was late after the World Cup. But Olivier can be very important for us like he was at the end of last season.
“If he starts scoring, it will be a good competition for them.”
Chelsea FC will return to Premier League action after the international break when the Blues take on Cardiff City at Stamford Bridge next weekend.
The Blues are currently joint top of the Premier League after having won all four of their opening games to set the pace heading into the new season.
Chelsea FC finished in fifth place in the Premier League last season and won the FA Cup under Antonio Conte.
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