Medel is Cardiff's record signing after arriving in south Wales from Sevilla in an £11million deal this summer and has made an impressive start to life in the Barclays Premier League.
The 26-year-old's disciplinary record has come in for scrutiny after he saw red seven times in 90 outings for Sevilla, one of which came after a clash with Swansea's former Real Betis midfielder Jose Canas.
And Rangel, in addition to stating Cardiff had paid too much for Medel, suggested he was the type of player that could be goaded into a rash action which would see him sent off.
Rangel had said: "He likes contact with other players. 'He's had an experience with Canas before, who got him sent off.
''That shows you that in these kind of games there are a lot of craziness and intensity.
''If you are clever enough you can get him sent off.''
Mackay wants there to be an edge to his team's play on Sunday, but believes Medel's clean disciplinary record this season shows he has the mentality to cope with the heat of the derby.
"He's got plenty to say usually", Mackay said of Rangel.
"He's much more experienced than me in these matters I suppose. Gary hasn't been booked yet so it shows he's not easily wound up so it's just one of these things. You are going to get that."
He added: "I've absolutely no doubts with these games you need a modicum of being calm and settled and being focused, but I do want that heightened sense of the derby game being inside them because having that little edge to them can really benefit them in these games.
"The atmosphere gives you it to start with it and we'll monitor it and make sure none of them are on the ceiling at that point but it's something you've got to embrace and enjoy."
Cardiff get the chance to face their fiercest rivals having earned promotion to the top-flight two years after Swansea's own ascension to the Premier League.
But Mackay insists watching Swansea's achievements of recent years, including last season's Capital One Cup triumph, placed no additional pressure on the Bluebirds.
"That had absolutely no part in my thinking last year. All our focus was on us. When you start thinking about others and what might happen then you are on to a loser," he said.
"We had to be very focused. There was enough problems in terms of beating 23 other clubs in the Championship and getting out of it.
"Last season was all about our focus and what we are going to do. It was something we were very focussed on.
"It's natural for people to compare the clubs. Obviously, we are the local rivals and everyone is realistic enough to know that they are in their third season in the Premier League and we have just arrived. I don't lose any sleep over that.
"Every derby you go into bragging rights are what sees the supporters through to the next game. That won't change on this one."