Jonathan Pitroipa, Jires Kembo Ekoko and Abdelaziz Barrada all struck from the spot for Ivan Jovanovic’s men, with UAE striker Salem Saleh also scoring from open play.
At the other end, Western Knights captain Makhete Diop converted from 12 yards for the hosts as part of his double.
The result ended a harrowing few days on a positive note after the Dubai side’s AFC Champions League run ended at the quarter-final stage amid continuing fallout from the Wanderley passport scandal.
The Brazil-born striker was absent once again for last term’s fourth-placed finishers because of the 60-day suspension imposed because of his “forged or falsified” Indonesian passport which saw him take the Asian place in the four player foreign quota.
But his new employers did not miss the summer buy from Sharjah’s presence as they raced into a 3-0 lead by half-time.
Barrada was felled by fellow Morocco midfielder Adil Hermach and Burkina Faso winger Pitroipa stepped up to score the spot-kick.
Saleh then slotted in from a wonderful Barrada pass, with Kembo Ekoko converting a penalty won by himself during injury time after his fancy footwork forced Hamad Al Hammadi into making a foul.
Dhafra were 2015/16’s grand succes story, rising from relegation fodder to eighth spot and a reaction came on the hour mark as striker Diop struck to make it 3-1.
But Al Hammadi was soon dismissed for a second booking earned in conceding a penalty, which Barrada notched. A remarkable game then got its final goal and spot-kick, Diop stepping up to finish it off.
