I think #1 is 100% Severino. The next one is tougher, but it almost has to be Mendick.
Can't lose Burger yet until Yoan is back. Sheets is the only real lefty thump we have on the bench, and he has hit decent so far this year.
You could go with a reliever, but Burr just got here, and you are already sending down a left in Severino.