Go to Scoring>Match Details/Teams.
Select the player you wish to replace:
Click on Replace.
A list of squad players will become available. Select the correct player and click Add.
Please Note: If you are in a league which uses League Registered Players (LRP) only those who are registered will appear as an option.
If the player is not listed, select Create New Player.
You can now create the player, boxes highlighted in Red are compulsory fields. Once completed press Add.