Christopher Coney launched the attack on the year-old tot while the boy was being pushed along a street by his grandmother.
Coney – who was stripped to the waist at the time - pushed the gran-of-two to the ground resulting in her losing control of the youngster’s trike.
The tot was left with scratches and bruises to his arms and body following the incident in Port Seton, East Lothian, last August.
Edinburgh Sheriff Court heard a half-naked Coney had been heard banging on windows in a communal stair just moments before he approached the 61-year-old from behind.
Fiscal depute Louise Hamilton said: “The accused exited the stair wearing only jeans and no top. He walked towards a parked car and struck the car with a pair of shoes.
“Around that time the complainer left her home with her one-year-old grandson who was on a tricycle. She also had a dog on a lead.
“The accused was walking and seen the complainer and immediately made a beeline for her. He barged into her from behind and she and the tricycle fell over.
“The child suffered scratches on his hands as well as bruising to his neck.”
Solicitor Paul Canavan told the court his 38-year-old client had been involved in “a bizarre incident” and he had suffered from “a history of mental health problems”.
Mr Canavan added Coney’s recollection of the incident “is more-or-less nil” and the incident “seems to have been a one-off”.
Sheriff John Beckett acknowledged the incident must have been “very frightening for the child” and that Coney had been acting “in an uncontrolled way”.
Sheriff Beckett told Coney, from Longniddry, East Lothian, he would be treated “leniently” by the courts if he stays out of trouble for the next nine months.
Sentence was deferred to October 3.
Coney admitted culpably and recklessly barging into the woman causing the tricycle she was pushing to tip over and strike the ground to the lad’s injury at Castle Road, Port Seton, on August 25 last year.
He also admitted to behaving in a threatening or abusive manner by striking a vehicle with a pair of shoes during the same incident.
A plea of barging into the woman on the body from behind causing her to fall to the ground was accepted by the Crown.