The 51-year-old victim suffered serious knife wounds to his leg after two men in a car jumped out and attacked the man as he rode his bike along Church Way shortly before 7.30pm on Sunday night.
South Yorkshire Police has confirmed that investigations into the incident are still under way.
The road was shut for several hours and scenes of crime officers cordoned off an area near to the rear of The Stag pub on Dockin Hill Road, with the man’s bike clearly visible leaning against a wall.
Numerous police cars and ambulances were deployed to the scene shortly after the attack.
Police have urged anyone with information to come forward and a spokesman said: “An investigation has been launched after an assault in Doncaster on Sunday.
“Police were called at 7.20pm to Church Way following reports that a 51-year old male had been attacked with a machete.
“Two offenders in a car are believed to have approached the man, who was riding his bicycle at the time, and an altercation has taken place in which the drivers of the car have attacked the victim with a machete.
"The victim suffered serious injuries to his leg which required hospital treatment.
“Enquiries are ongoing to identify the offenders.
"Anyone with information about this incident is asked to call 101 quoting incident number 752 of 16 January.”
Drivers were diverted away from the scene, with investigations taking place long into the night following the attack.