British media reports are continually linking the club with the signing of Dominic Solanke.
Asked about the Bournemouth star, who is said to be likely to join the club in the coming days, Postecoglou was vague.
He told reporters: “I don't think we've been looking to replace Harry. I think I said a number of times last year you can't replace a generational player and there's a reason they stand apart. It's fair to say front third is an area we really believe we need to reinforce this year. We've been working hard to try and get the right kind of players into those areas we need for another challenging season ahead.
“We're back in Europe, which means more games, and the one thing coming out of last year when we had disruptions in terms of injuries or suspensions there was a real drop off and we want to sort of try and mitigate that this year by having a stronger squad to cope with everything we do.”