A couple of strategies to try out:
1. Stongest 2 players for the current turn get 2 batons each. This could mean that the blaster gets 2 batons - or that they only get 1, and the 2 players strongest @ 8m get 2 batons.
2. Coldest player sits out. In this strategy, 3 players get 2 batons and the fourth player sits out the turn. This could be that their strength isn't needed (e.g. a blaster w/o field kubbs) or that one of the players just isn't feeling confident/comfortable, and they sit back a turn, or until one of the other players needs a break.
Overall, in terms of keeping everyone fresh and strong, having 4 players in a 3player tournament has substantial upside.