The 23-year-old took and 18-point haul to no doubt put his name into the minds of the selectors ahead of the RBS 6 Nations next year and challenge Sexton for the jersey for both club and country.
Madigan was named man of the match and after an outstanding display of control, invention and nerveless place kicking Gibbes backed the Irishman's commitment to the cause.
"There's two things I really like from him," Gibbes told the Irish Independent. "He's coachable, he's playing at a really tough position with a lot of responsibility.
"He doesn't get everything right, but he cops his feedback on the chin and then he puts his head down and works hard off the field during the week. He continues to work really hard and that's a positive.
"And the second thing is I actually think he is reasonably brave. He will give it a go and I think the forwards definitely respect a No.10 that puts his head down in the dark places."
Madigan was given his chance to shine thanks to an agreement between the IRFU and the clubs in which established internationals must be rested for a set number of games.
And Gibbes admits it adds an extra element of tactics to the season.
He added: "I think you have to balance. We have to choose which games they can play and we have to manage them.
"We have to see what is best for the team so we can filter them in during the next few weeks."