Tempers often flared in a match which Darlington dominated even before the home team were reduced to 10 men.
The Quakers could have gone in front in the first minute when striker Adam Proudlock forced a good save from Clayton Ince following an error by full-back Chris Palmer.
Two minutes later Rob Purdie tested Ince with another shot and Proudlock's shot on the rebound was cleared by Anthony Gerrard.
It was against the run of play when Ricketts found the target with a free header from an excellent free kick by Palmer, but the former England striker hung his head in shame on 16 minutes when shooting woefully over after Richard Taundry had seen a shot saved by Simon Brown.
Darlington were playing some neat football with wingers David Poole and Adam Griffin giving the Walsall defence plenty of headaches and it was no surprise when the visitors drew level in the 31st minute.
Poole outpaced Netan Sansara for the umpteenth time and sent over a wicked cross which Griffin pulled back for Jason Kennedy to hammer home a great shot from just outside the box.
Seven minutes later Ricketts received his marching orders and it was all uphill for Walsall after that, although lively striker Jabo Ibehre almost forced a chance for Alex Nicholls, but the young winger couldn't quite get to the cross.
The Quakers remained the better side in the second-half and took the lead in the 67th minute when Poole beat rookie fullback Sansara yet again and crossed the ball for Clarke.
His first shot was blocked by substitute Manny Smith but he made no mistake second time around, firing home from the rebound.
In the dying minutes Walsall keeper Ince saved well at the feet of Purdie, while at the other end Simon Brown produced a good stop from substitute Troy Deeney.
Tempers flared in the closing minutes and even when the final whistle had blown there was a melee in the penalty box which resulted in Gerrard being booked for dissent.