Williams impressed on his return from a long-term injury in the 1-1 draw with derby rivals Mamelodi Sundowns, making a number of saves at Lucas Moripe Stadium on the weekend.
Former Kaizer Chiefs goalkeeper Reyaad Pieterse was previously in goal for the 2017 Confederation Cup finalists.
"Ronwen's return was not by chance," said Tinkler.
"This was the date we had set if I can tell you over a month ago. We said he would be back at least for the Sundowns game. It was not for other reasons that he played [against Sundowns].
"We knew exactly how long his recovery period would be. We knew how long his training programme would be. We said he would be ready either for Platinum or Sundowns but we opted to give him another week and bring him for the Sundowns game. I thought he made hell of a great saves."
Matsatsantsa are five points above the drop zone in 12th place on the table with eight matches left. Tinkler believes a top-eight finish is a realistic goal for the Tshwane giants, whose domestic form plummeted after their CAF exploits.
"Realistically I have to finish in the top eight and in my mind we can't accept anything less than that. Where we finish in the top eight will depend on results but that has to be our prime objective."
The former Cape Town City boss made it clear the league is SuperSport's priority going forward.
"The league is the most important. It's not a case that we are not gonna take the CAF Confederation Cup seriously, it's a competition I like playing in. It's a competition we would like to go again as far as I have been before but our priority has to be the league right now. If you asked me if I would field a strong team [in the Confed Cup], probably not because of everything experienced, so it will be a great risk for me."