Top pair and all that it blooooooooooooooooooooows in this game.......

[Small Fry]

Knowing your opponent can be a big help here. And you did excercise pot control. For example: lets just say blinds are 1/2 and you made a preflop raise of 7. With the one caller (blinds folded) the pot is 17. Flop you bet 12 he calls. Pot is now 41. If the turn gets checked the pot on the river is still 41. But if you throw out a 1/2 pot bet on the turn and get called the pot on the river will be 81. This will cause any bets on the river to be much larger.

A few more points for you. I would very rarely fire a 2/3 size bet on the river with only TPTK. This is very opponent dependent, but think about it. What will he call this large of a bet with. Going back to my example the pot was 41 and you fire out 27. Its a great value bet if you feel your opponent will call with TPWK or second pair, but if he'll fold these then all he's calling with is hands that beat you. And if he's tricky and reads your check as weakness he might raise to pressure you. IMO the one good thing about your large sized river bet is that if a player wants to raise you they'll need to put in a decent amount of money so it discourages thes bluff, so in my experience they have a pretty good handin this situation. What I think is a real good option (again very opponent dependent) is to check again on the river to induce a bluff or a weak value type bet that you can easily call. Pot was 41 so opponent might bet anywear from 15-30 but you can definitely call this bet.

On goal in NL to keep in mind is to try to keep your decisions as simple and easy as possible. Betting the river oop with TPTK and getting raised complicates matters.

Good Luck