Soooo…I don’t post much in the comments but decided it’s high time I start learning through hand history and the more hand history reviews the better.  Having said that, I hope you don’t mind me jumping in here.  Take it for what it’s worth.  

Looking at that board, my first thought was that I don’t think you calling on the flop was a good option.  I think if you were going to continue and represent when a scare card hit the turn, I think raising may have been a good option on the flop.  I also think folding on the flop was a good option too, but again not sure about calling.  That’s such a wet board.  MP is pretty active and aggro according to the numbers so I do understand why you wanted to play against him with this hand, knowing if you hit he will put more money into the pot.  

I also think if you check raise, there are a ton of turn cards that give you more outs heading into the river, any Q,K possibly your A is good if he has a hand like JT, obviously an 8 is good for you and a diamond is good. 

When you call the flop, I think I would put you on a hand like QT, QJ, maybe flush draw, maybe JT, 77s, 88s.   You could have 8T…but maybe in villain’s mind that is the only hand that is beating him on the turn.  I think once he calls the turn, he is committing himself to the river call.  

I think just the way the hand played out he was going with the 99s… but again, my initial gut is to fold the flop.  

Sorry if I’m all over the place…I keep going back to I think folding was the best option in my brain, but trying to help you along in the hand the way it was played.