The 22-year-old midfielder has been training with the club for a while now and featured in the last reserve match, while playing alongside fellow trialists Yazid Kaissi and Gary Smith in a behind closed doors match against Walsall yesterday.
Mills had earlier said one trialist had impressed him in particular, and it now appears that man was McHugh.
McHugh was playing for Bradford earlier in the season, making 5 appearences for their first team in nine month's at the club, while he's also had spells at Swindon, Gainsborough and crucially, a side then run by Gary Mills, Tamworth.
He will be keen to impress for the Notts, as it looks his last real chance of getting a regular shot in League football. McHugh is expected to fill the void left by Michael Brough, who was released by the club yesterday.