The rock-bottom Team of Choice are coming from a 1-0 defeat to Kaizer Chiefs, a result Tinkler admitted was "expensive" for his team in their fight for survival.
Tinkler is hoping to see a different mentality against the defending champions, who are also gunning for maximum points after dropping five points in their last two league matches.
Speaking after the loss to Chiefs on Saturday, the former Orlando Pirates coach said the character of his players will be tested at this stage of the season and they need to start being fearless if they want to survive.
"We are still playing out of fear, but we can turn negatives to positives, we just need to be motivated," he said.
"This stage of the season is where we see the true character of human beings, taking responsibility because the harsh reality is that we are responsible for the situation we find ourselves in."
Tinkler also feels the team needs two straight positive results to change their mindset and believe again.
"We need to get positive results in two straight games so we can be in a good spirits again," he added.
A win for Sundowns tonight would see them return to the top of the table and go three points clear, while for Maritzburg three points would still leave them in the relegation zone. They are four points from safety.