Maybe Rafa is bringing Lejeune and Semedo in to compete with Clark and Lascelles, with plans to switch Mbemba to DR or DM, or to move him on? The new lads started out as DM anyway so they could be an option if Hayden is unavailable.
Anyway, the window hasn't opened and we are already having progress with a few players. That's some improvement over the past and will give Rafa more preparation time to gel them into the team.