And although Leinster have only won once in their opening four fixtures under new coach Joe Schmidt, McGahan is not taking their rivals for granted this time around.
"I think it is important to look back in more detail at those ones we lost rather than the ones we've won," said McGahan.
"We need to look back and gather ways of seeing what their theme was in breaking us down.
"We need to look at ourselves as well because a lot of it was our own undoing, as regards our set-piece and high numbers of turnover ball.
"They are under new management and have a new game plan and the amalgamation of both those things means we will, I'm sure, maybe get a bit of the old on Saturday."