At the start of the month, the 25-year-old was playing in the shadow of injured Mike Edwards, and looked far from up to the job, as his deputy.
But, with the long-term injury of club captain Edwards, Thompson was forced into action.
After a shaky start in the Magpies back four, Tann has since grown into his position as a fans favourite.
He may not be the most composed and classy of defenders, but what he has an abundance of is, awareness.
He reads the game superbly and time and time again has produced vital tackles, blocks and headers over the course of the month.
After a string of fine displays alongside Stepehen Hunt, he has earned the respect of the County crowd.
Fine performances against Rotherham, Hereford, Chesterfield and Dagenham have helped Notts pick up form.
His defensive showings see Notts a lot better off then they could have been.
He may not keep his place at centre-back after the return of Edwards but he looks likely to claim a place at right-back over an incosistent Lee Canoville.
And, a taste of life in the centre, will put him in good stead.
Tann joins Richard Butcher with the NCM gong after Butcher won the award for a fine August.