The Blues have failed to secure a Premier League victory since Benitez took the managerial reins on 21 November in the wake of Roberto Di Matteo's controversial sacking.
And they were knocked out of the UEFA Champions League on Wednesday night despite a thumping victory over Nordsjaelland, becoming the first European champions to exit the competition in the group stage.
The Spaniard's disappointing start to life at Stamford Bridge had led to rumours that Grant, who was in charge for the dramatic Champions League final penalty shoot-out defeat to Manchester United in 2008, would be offered a second stint.
But the Israeli said: "Nobody from Chelsea has offered me this job. I heard a rumour but I think this is not what's important.
"What's important is Chelsea have a manager and the club need to support him and not look for any other things.
"I don't think it's the right idea for the moment. I don't like to speak about myself now because I have other things to do at this stage.
"I think Benitez is a very experienced coach and manager and I don't think a few weeks after they give him the job he will leave and I don't think it will be right.
"He needs to use all his experience to take the club in a different direction and they need to do everything to support him and not to look around."
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