Truly shambolical marking assignments for that one- Romero as captain should be ensuring our best aerial defenders are marking their most dangerous aerial attackers EVERY time. There's no alternate universe where Johnson should be marking Matijs DeLigt- a situation that should have never been allowed to happen.
That being said, he somehow ended up being Johnsons mark, and Johnson completely failed to track him. Johnson is simply NOT the kind of player that is going to fight his way around screens. His optimal position in set pieces like this is sitting outside the edge of the box trying to run the counter after winning possession, or closing down oppo shooters from deep if the ball ends up outside the box. He's not a player that should be marking aerial threats inside the box.
I find it shocking he somehow ended up being DeLigt's marker. Would be comical if it wasn't us.