Officers from the Broomhall Team arrested the alleged offender, and hope city centre CCTV will assist in the investigation.
A spokesman said: “The Broomhall Team are on Saturday night city centre patrols.
“One male is under arrest for an unprovoked assault.
“Thanks to the quick response from the city centre cctv, the team are now starting an investigation
“The only arrest from the city centre night time revellers so far.”
Anyone wishing to report a crime should call South Yorkshire Police on 101.