Jackson, whose goal secured the Addicks a 1-0 victory against the Owls at Hillsborough, found the net after 21 minutes following a foul by Neil Collins on Danny Hollands.
The goal was enough to give the Addicks victory and extend their lead at the top of the League One table to seven points.
But the game ended in controversy as referee Darren Deadman issued red cards to both Charlton substitute Darel Russell and Blades substitute James Beattie.
Russell was sent off for a challenge on Kevin McDonald and Beattie was ordered off for his part in a subsequent melee.
The Blades had a ‘goal’ controversially disallowed in the 40th minute when Charlton goalkeeper Ben Hamer pushed the ball into his own net at a corner.
Referee Darren Deadman awarded a freekick to Charlton - sparing Hamer’s blushes - but it was hard to understand why without the benefit of video replays.
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