Jesus Datolo tucked away the resultant spot-kick but the hosts failed to capitalize on their extra player as Gimnasia held on to secure a point.
The result left Maradona’s outfit 22nd in the 24-team standings with three wins, two draws and 10 losses. Banfield remained 17th, six points above Gimnasia.
Maradona, 59, took charge of Gimnasia in September when they were last in the standings with just one draw from five matches. The 1986 World Cup winner has led the team to three wins and a draw in their past seven matches.
In Friday’s only other Superliga fixture, Defensa drew 1-1 away to defending champions Racing Club.
On Saturday, league leaders Boca Juniors will host second-placed Argentinos Juniors at La Bombonera.