What's this talk about Garnacho's pace? He's lacking in it, it's why he has to stay wide despite being in a position the manager wants a central player, because without a running start he doesn't have the pace to beat a man.
His lack of pace is one of the main reasons, along with his inability to get his head up, that he never has much time and is so wasteful in terms of shooting or playing a final ball. His shortcomings were perfectly demonstrated just before the sending off when he had the box, had an opportunity to shoot or play in Hojlund, but by the time he'd gotten his head up to see where he was and who was around him the defender had recovered and tackled him.
He's much better coming on as an impact substitute, being fresher than the opposition makes it easier for him to get past them and gives him the extra second to get his head up after a run, but as a starter he'll need to fundamentally overhaul how he plays to be effective.