The North London club were being linked with Yang Min-yuk from South Korea.
Asked about the deal, and if captain Son Heung-min has any involvement, Postecoglou told reporters:
“Yeah, again I'm well aware of the quality of the K League. When I was at Celtic we were looking to bring over at least a couple of Korean players at the time and I think they've brought a couple over.
“Again they 've made a fantastic impact in Europe, a lot of Korean players, none bigger and none better than our own Sonny. He's just an outstanding player and an outstanding person.
“He's the captain of our club and he's just an outstanding individual, we're super happy to have him at our football club. So yes, we'll be looking far and wide for players and as you rightly said, it is difficult for me to discuss (grins).”