51-year-old O'Connor, who had a couple of playing spells with the club - making over 140 league appearances - is no stranger to the coaching structure at Banks's Stadium having enjoyed a less-than-successful spell as Assistant Manager to former Walsall boss Chris Hutchings.
With the team currently struggling near the foot of the League One table Keates was said to be keen to add another voice to the training sessions with O'Connor bringing a wealth of playing, coaching, and scouting experience which will no doubt benefit the Saddlers somewhat young squad.
Speaking via the Express & Star, Keates both confirmed and welcomed Martin's arrival, he said; "From the first day I have always wanted to add another member of staff. It’s something I have been chipping away at for the past few weeks. Martin has had other commitments so he had to get things in place.
"But he is somebody I know well. I have known him for years, I have played alongside him, I’ve shared a changing room with him. As a person he is a great person.
"He is very vocal and it’s a different voice, he will help freshen things up. It can’t just be me and Andy all the time. For me, it is a great addition for the club going forward."