Rangers head coach Danny Rohl tells BBC Scotland: "At the moment, the feeling is more disappointment because you dropped two points after a 2-0 lead.
"It's not about 50 minutes, it's about longer. We had high intensity, we played really nice football, we found our space. It was great.
"In the second half, we were not clinical in possession. We made some wrong decisions then we lose the ball, we give them a little bit of momentum then they score early in the second half and then you know it's 2-1 and they have nothing to lose.
"Finally, it's a draw. It's always a little bit lucky for a team to get a late pen. This is normal, I would say it's the same when we get a pen late in the game. It's about the next game and we have to move on.
Celtic interim manager Martin O'Neill tells BBC Scotland: "It was obviously a great game. We were well and truly second best in the first half, for almost all of it. They got off to a great start.
"The second goal wasn't great play by us, however. It was a long way back at half-time, but this side has shown a great determination, got the ball down and played.
"The second half belonged to us and we got an equaliser which we thoroughly deserved.
"If you're 2-0 down at half-time, you have to question yourself. I spend my life questioning myself, to tell you the truth. But anyway, we pulled it round second half. Great effort by the players, they've shown great spirit."