The 1,691 crowd witnessed a determined comeback and Stevenage quickly worked at addressing the arrears. Touncara had already gone close with a deflected attempt when Charles smashed an angled drive beyond Johnstone on 55 minutes.
The United keeper got the better of Tounkara to make a splendid one-handed stop but was powerless to prevent a blistering left-footed drive from Charles levelling the scores. Suddenly, the Reds were clinging to parity as Sam Wedgbury fired over following a James Dunne run and Johnstone pulled off a reflex save to thwart Tansey with Charles spurning the rebound.
Barmby hit the side-netting as Butt's youngsters looked for a winner themselves but Freeman passed up the best opportunity to clinch victory with only three minutes remaining when firing off target.
United: Johnstone; Love, McNair, Grimshaw, Rowley; Weir, Rudge (Harrop 67), Rothwell, Barmby; Byrne (A.Fletcher 82), Wilson (Adarabioyo 65). Subs not used: Gollini, C.Evans.