Founeke Sy halved the deficit in the 18th minute after Gyan's double, but further goals either side of half-time from Mosallem Faiz and Mohammed Abdulrahman clinched a comfortable victory for the visitors.
Dubai SC also picked up three points on the road - to go top of the fledgling standings - but needed a late winner from Richard Candelaresi to claim a 3-2 success after relinquishing a two-goal advantage at Al-Sha'ab.
Simon Feindouno opened the scoring for the away team three minutes before the interval and Candelaresi doubled their lead six minutes after the restart.
Ricardo and Nasser Khamis got the hosts back on level terms by the midway point in the second half, before Candelaresi's second goal of the match 15 minutes from time proved decisive.
Elsewhere, there were 2-0 wins for Al-Jazira - at Al-Ahly Dubai - and Bani Yas at home to Al-Ittihad Kalba.
Matias Delgado were the men on target Ibrahim Diaky in either half for Al-Jazira while goals in the first 25 minutes through Ismail Muallim and Andre Senghor won the points for Bani Yas.