Sergiño Dest is an extraordinary and extremely exciting addition, but it doesn’t mean Sergi Roberto will give up on his role. While both played in midfield in the past, they have completely different skillsets and are in very distinct stages of their careers, so Ronald Koeman will have two interesting alternatives from which to choose.
As seen against Celta, Sergi Roberto still has a lot to offer. Not only was scoring a goal and saving another one what made him have an excellent performance, but his support in transitions, defensive solidity, and positional awareness to push high and know which spaces to occupy. It is not easy to live in the same side as Lionel Messi and Antoine Griezmann, with the latter then sent off and Sergi having to be the main winger, but he understood what to do at every moment.
This is the advantage he has over Sergiño Dest, who, by contrast, is more exuberant, better individually and more technically gifted. But also more raw and at times impetuous, and not as caring in his occupation of zones as Sergi. It seems like Koeman likes both players, but the Catalan will surely continue to be very useful with his maturity, versatility and positional intelligence.
Sergi needs no adaptation, and I see him starting in most of the big games approaching. While Koeman seems to admire Dest and he is not afraid to use youngsters, don’t expect him to throw him in if he’s not ready. I predict Sergi to start in the next big clashes against Sevilla, Getafe and Madrid, and Koeman to be alternating afterwards as there will be quite some competition at right-back.