Ten teams play elimination, how to play in the second round?

If it is a single knockout, when there are 5 teams left in the second round, the following methods can be adopted:

1, draw lots, 1 team bye, three teams in the next round, draw lots, and there will be a team bye in the final (you can also draw lots for bye places among the two teams without bye in the last round).

2, draw lots, add a round to grab the number, play a round by the unlucky two teams, decide the semi-finals, and then draw lots.

3. 10 team draws lots in the first round. Team 4 grabs the number and plays one round, and the second round is tied.

If a seed team is set up, the seed team can not grab the number, or it can have a bye in the first round.