The Black Stars captain who was playing his first game in over a month converted a second half penalty to earn the spoils for the Boss at the Hazza Bin Zayed Stadium.
Al Ain fell behind six minutes into the restart with Tariq Ahmed giving the visitors the lead.
But Gyan stepped up to convert a 77 minute penalty and went on to play for full throttle to prove his fitness.
Al Ain failed to build upon the momentum to ultimately drop vital points at home in the Arabian Gulf League.
Zlatko Dalic’s side are now placed d6th in the league but crucially with a game in hand.
The former champions will next travel to face Al Ittihad Kaiba in the league.