Which means he'd be out of the UEFA Cup first round first leg tie against Metalist Kharkiv and would more than likely miss next Sunday's clash with Aston Villa.
And that would be a big blow to Everton as the Dane came on and changed the course of the last match at Bolton.
But, despite the gloomy scenario coming out of the Denmark camp, Everton's medical team are still hopeful that Gravesen will overcome the problem and be able to figure in Saturday's 12 o'clock kick off.