Rather stay away from Atletico and their players for now. You never know if we buy another big flop that most likely over-performed because of Simeone's genius. Chelsea did the same mistake as us twice while Cerezo is laughing all the way to the bank.
add to this I really think Koke is flourishing under Simeone tactics just like Arda Turan did. Take him out and you won't see similar performances. It's madness some here rate him above Verratti and Pogba. We will see his performance today with the NT.
I am slightly concerned about this part too.
Arda really looked like a beast there.
While currently in Barca and even in Turkish NT, he is insanely poor.
So:
1. either Arda had "Atletico" effect
2. or he lost his stamina
3. or both 1+2
Koke hasn't lost his stamina, but "Atletico" effect has to be considered.
As Thwix said, really majority of Atletico's players play way, way weaker once they leave Atletico.
I would like to see more from Koke, now when he'll play for an NT team, in a different formation+system, when he is not surrounded by Atletico's teammates.
If he'll play on this Euro with Busi+Iniesta around him, that could tell us way more how he fits into Barca's system and with our type of players.