Jerel Ifil picked up Aberdeen's fifth red card in five matches after he aimed kick at Samaras.
"But we managed to get he breakthrough and got there in the end.
"Aberdeen have some very young and talented players, but we managed to get on top of them, which is important because they have a lot of legs and enthusiasm.
"Thankfully for us, we managed to use the quality we've got to keep the ball off them for long spells.
"At Celtic Park, we've got to be confident, and generally we are. Even through the periods where the results weren't going, that's why I say regardless of dropping points, the performance of the team was very high."
Aberdeen boss Mark McGhee: "The only complaint I have with Jerel Ifil. Of all the red cards we've had, it's the first I felt was warranted.
"It was stupid, reckless and unnecessary.
"It cost us a chance of getting back into the game. It gave us no chance.
"He could lose his place in the team. It really was stupid.
"We didn't exactly have a mountain to climb, but we were having a difficult time - but after the sending off, we had no chance."