Clottey converted a penalty on 71 minutes after he had been fouled by goalkeeper Robert Kidiaba. He then equalised 13 minutes later with a superb solo effort, running onto a long pass from midfield, cutting inside several defenders and firing the ball past Kidiaba into the far corner of the net.
It was all Mazembe in the opening half of the Matchday 2 fixture, and captain Tresor Mputu scored twice to leave the four-time African champions in comfortable position at half-time.
Mputu applied the finishing touch to a swift attack with a low close-range shot on 11 minutes and doubled the Ravens' advantage just past the half-hour mark when he scored from the rebound after his penalty kick was parried.
Berekum Chelsea defeated Zamalek of Egypt 3-2 in Accra two weeks ago, while Mazembe lost 2-1 against record six-time title holders Al Ahly in Cairo.