Paratrooper Barry Cox was one of several Wigan Athletic fans who ran onto the pitch after their team scored an injury time winner against the Saddlers on February 20.
Prosecutor Kulbir Paul told Walsall magistrates Cox was approached by Walsall steward Dave Garner who attempted to usher him back into the stands.
Cox, of the 3rd Battalion, Parachute Regiment, then elbowed Mr Garner in the face who escaped with only slight reddening, the court heard.
After hearing about the 29-year-old's military career – which includes four years in the Royal Navy – magistrates decided to impose a conditional discharge.
His Lieutenant, Henry Mitchell, told the court Cox had always maintained high standards and has both Afghanistan and Iraq campaign medals.
He added Cox could be posted around the world at very short notice.
Lt Mitchell said: "He is an intelligent soldier who has shown full remorse and understands the severity of the issue.
"He understands his actions can bring the army into disrepute and the effect this could have on his career."
Cox pleaded guilty to entering the pitch and common assault.
Defending, Nayan Patel, said his client had not been sure who Mr Garner was when he approached and Cox 'caught' him.
Cox, of More Street, Newtown, Wigan, was given a conditional discharge for two years and ordered to pay £150 compensation to Mr Garner, £135 costs and a £15 victim surcharge.