The SPFL Premiership club has asked for permission to speak to the Northern Irishman who spent two spells as a player at Ibrox.
But Paul Hartley will have his former Raith Rovers and Millwall mentor alongside him when he takes Falkirk into Tuesday’s red-hot atmosphere at East End Park, Dunfermline.
The Bairns boss said: “Rangers have asked to speak to Jimmy so we’ll see how things develop over the next couple of days.
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“We have given him permission for talks and we’ll know within the next couple of days if he’s going to take the job.
“He’ll be with me until Tuesday at least.”
Hartley though has only had Nicholl alongside him for two months and admits the news caught him by surprise, but he would not begrudge the former Ibrox defender a move back to Rangers.
“It’s come out the blue.
“I’m disappointed with losing him but I see the other side of it. He was out the game for a long time in terms of coaching. We brought him in but it’s one of these opportunities.
“We’re not here to stand in people’s way.
“I’ve enjoyed my time working with him - I hoped it would be for the next couple of years but things happen in football.
“If things move along for him we wish him all the best.”