Possible colluders in a home game?

[LetsRock]

I'm involved with a great group of people who play in a weekly NL Hold'em home game. The core group is a lot of fun and we've never had any problems of any kind.

Last week we had a couple of new players come to the game. We were running a 2 table tourney and welcomed 2 fresh bodies.

These 2 busted out of the tourney pretty early, but in the cash games that followed, these 2 guys had a very strange pattern about them. I'm not sure if they were just complete idiots and one of them was running hot (he was) or if they were working us. (One guy left well ahead, the other broke, but the winner's take wasn't a whole lot ahead of their combined buy-ins.)

It didn't occur to me til the next day (I was very tired from a long day) that something felt odd about their patterns. With the exception of one part of the session (And they were both running cold during that stretch), these guys always sat in the same position related to each other (even after a couple of table changes) - Player A (the big winner) just to the left of PLayer B. (For the tourney, they happened to be randomly seated that way.)

On many occasions, Player A would limp re-raise from early or middle position after several players had come in and a late position player would raise (one guy was constantly raising). Then player B would double player A's raise making it a really stupid call unless the rest of us had very premium cards. It would often wind up with the two of them head's up and many times, Player B had pretty poor cards (one time he had something like a 54o). They would keep betting, when they had the pot head's up (which seemed to make their play "clean" at the time) and usually Player A would bust his buddy. They also would take "planned" smoke breaks together outside my garage, even though many of us were smoking in the garage as were they.

I spoke with the other solid, experienced players who were there and none of us could clearly put a finger on collusion, but we all felt that the possibility was there. We're going to invite them back and watch them really closely this week (we'll have 4 sets of eyes on them).

I don't have a lot of experience with possible cheaters. One of our experienced players is confident that he can spot their ploy quickly if they're up to something, but I don't know exectly what to look for. They could have been kicking each other under the table or just using that betting pattern as a signal.

Has anyone ever witnessed such a paattern? What specifically are we looking for to bust them if we do suspect that they're working us?

Thanks for any input.