Wasted too much time chasing Giroud and now this? We did the same last season, just need to go after a realistic target and get them in now rather than mess about with things like this, it's just not going to happen.
We aren't chasing him. This story is based on an offhand comment in the pre-match press conference because we're playing Chelsea and it's the end of the transfer window.
Asked would we take Costa, what's he going to say? Sure.
It doesn't mean we're doing anything about it.
He's going to Atletico, as he's done with Chelsea and seemingly unhappy in England as a whole. Atletico are allegedly even going to pay his fines while he's staying out in Brazil, probably because it's way cheaper than paying the fee Chelsea want for him. He's not coming here. Koeman knows this.