That's the irony! I too have seen how Koeman was quick to take off Griez and Dembele in the 60th minute when they were starting (which I had no problem with), but when it comes to subbing them on during the classico while down a goal, he was dragging his feet. IMHO, Coutinho had been super effective and exciting in earlier matches this season playing in a central role, just not classico. He was on the left and looked a bit like the one dimensional Coutinho of 2018.