OK, you are allowed to trade upto three players before June 30 - any three players you want, whether injured or not.
However, in order to ensure a competitive DuFFLe for the entire season, if you have a player that is unable to be selected, for any reason, for a period of six weeks or more, you may trade them out of your team and these trades do not count towards your 3 trades mentioned above. These additional trades are referred to as LTI (Long Term Injury) trades. Once you trade a player under any trade system (LTI or 3 by 30 June), the player is no longer in your team and you have no further claim to them.
So, if Hodgey is out for 6 weeks you can trade him out, but then he is gorn from your team and someone like me can select him whenever they want, with a quality player like Hodge, many including myself, would happily trade him in immediately and carry him in the team for the duration of the injury. This is what Biz is doing with Beams - he is holding him until he returns, however he can trade him under LTI anytime he wants, but is way better off holding onto him -as you are with Hodge.
I note you need a ruck. I would hold onto the ruck you are planning to trade, just in case he comes good later on - as you have noticed Rucks are in very short supply and high demand - you may be better off trading a player who you don't think will be consistently good enough to warrant continued selection in your team, keep your crap ruck (just in case) and bring in whatever is left - i.e. Hampson is only playing due to Maric's injury - he wont be a consistent starter for your team.
Good Luck. You can still trade Hodge if you want, and Merc will confirm that he is mine if you do so.
