Other than private-message to your team mate to encourage them to play the tourney game, not too much.
I would also advise the team leader to accept requests as soon as possible and also p.m. the new crew member to let them know they've been accepted to the team so they can start spinning. If the team captain doesn't notice someone who's asked to join the team soon, the requester may forget all about the tourney or think they will not be accepted.