[adsman]

He probably has a hand like A8 or QT that whiffed but he wants to take one off. If you've seen him calling the flop and folding to a turn bet before then bet away. He's passive though so there aren't any problems with checking the turn as he probably won't bet into you on the river. This pot is very small. There's not a lot of point in throwing more money at it with the second nut low if this guy is going to call you down.