The Frenchman is the latest name linked with the City Ground hot-seat.
Forest's City Ground
Another day, another manager linked with Nottingham Forest.
But what do we know about him? HITC investigates...
5) Age 51, Montanier is a former goalkeeper with French sides Caen, Nantes, Toulouse, Gueugnon and Saint-Etienne.
4) He retired in 2000 and landed his first managerial role four years later with Boulogne.
3) He was promoted with the Côte d'Opale outfit in 2008-09, but left for Valenciennes ahead of their top flight debut.
2) Having led Les Athéniens to back-to-back mid-table finishes, Montanier moved south of the border to Real Sociedad, whom he led to fourth in La Liga - and a Champions League place - in 2012-13.
He was subsequently awarded the Ramón Cobo trophy, given to the league's best manager, by the RFEF coaches committee.
1) But, as he did at Boulogne, Montanier chose to quit while he was ahead and left at the end of his contract, becoming the new manager of Rennes.
Back in France, the Norman secured 12th and ninth-placed finishes, but left his post in January, with Les Rouges et Noirs sixth in the standings, following a shock cup defeat to Ligue 2 Bourg-en-Bresse.