Molon Baraka pounced on the terrified woman as she walked through Glasgow Green in January this year.
The asylum seeker pinned the 51-year-old to the ground, but she bravely tried to fight him off.
She was able to get into one of his pockets and snatch a number of personal items -including a library card which allowed police to trace Baraka.
Officers later found him at his flat in the city's Bridgeton, hiding in a cupboard.
The 26-year-old is now behind bars after he admitted at the High Court in Dumbarton to assaulting the woman with intent to rape.
Married Baraka -originally from Sudan -will learn his fate next month.
The court heard how the attack happened as the victim made her way to work in the early hours of January 5 this year.
Baraka approached her in Glasgow Green and initially asked her for a cigarette.
He then said "money" and "sex", but the woman ignored him.
However, prosecutor Gillian Wade QC told the court how Baraka then grabbed his victim and dragged her towards an area of long grass in the park.
Baraka eventually pinned the woman to the ground and demanded she be quiet.
But she managed to fight back.
Praising her bravery for fending off Baraka, the QC added: "She showed courage during this sexually motivated attack on her."