It got better for Charlton minutes later when Kermorgant was again influential as he raided down the right and put in a lovely ball across the face of goal that was turned into his own net by Rhys Williams.
Chris Powell's side almost go their third goal of the match when Pritchard found Kermorgant in space on the edge of the box, but he could only curl his effort just wide of the post.
The home side tried to get back into the game but substitute Scott McDonald missed the target from close range, scuffing his shot wide.
Middlesbrough did get a goal back when Marvin Emnes was played in behind the Charlton defence and he made no mistake in slotting the ball past Hamer.
Tony Mowbray's side completed their comeback with a late goal from Scott McDonald as he headed home Mustapha Carayol's cross to earn his side a point.