The promising young defender rose effortlessly in the 75th minute to head home Daniel Fox's corner.
It was justice for the battling Saddlers who had been the better side for long periods in the first half, but had fallen behind to a goal from Jason Price shortly before the interval.
Walsall keeper Clayton Ince, usually immaculate, saved a shot by James Hayter but could not hold on to the ball and Price followed up to scoop the ball into the net.
Walsall ought to have made more of the chances they had created prior to that. Striker Michael Ricketts, who had a fine game but lacked support, fired just wide from Darren Wrack's 34th minute pass.
Five minutes later Edrissa Sonko had a gilt-edged chance from a cross by Ricketts, but headed hopelessly wide when all on his own in front of goal.
And four minutes before the interval Fox sent over a dangerous corner, but Mark Bradley headed over at the far post.
Doncaster, moving the ball about superbly, began to build up the pressure and, in the 43rd minute, Price was given a chance by the lively James Coppinger but missed under pressure from Ince.
In the second half it was end-to-end with both sides looking full value for their lofty positions in the League.
A minute after the interval Ince fumbled a shot by Hayter with the ball going out for a fruitless corner, while at the other end Sonko was wide with an angled shot after Ricketts had won the ball.
Walsall might have been further behind in the 63rd minute, but Ince tipped over a shot from Brian Stock.