Hull will be forced to spend nearly all of their Shane Long windfall if they are to land Blackburn's Jordan Rhodes as his replacement.
Scotland striker Rhodes, who has scored 53 goals in 99 appearances since joining Rovers two years ago, has emerged as Steve Bruce's No. 1 target but will not come cheap after Blackburn rejected an initial offer.
They want a profit on the eight million pounds they paid Huddersfield and value their prize asset in the same bracket as Long, who joined Southampton in a surprise 12 million-pound deal earlier this month.
Hull's Europa League trip to Lokeren this week has complicated matters, with Bruce admitting after the match on Thursday he did not know how far advanced the discussions over Rhodes were.
Blackburn, meanwhile, have indicated that the ball is in Hull's court and await an improved offer.
Rovers, who signed Tom Cairney and Corry Evans from the Tigers last year, are understood to be interested in Bruce's son Alex as part of any deal.
Bruce would be hesitant to sanction that, with the centre-back having impressed last season and also started in the team's Premier League win over QPR on the opening weekend.
Hull favour a 3-5-2 formation, meaning Bruce senior would be loathe to lose one of his established central defenders.
Speaking after the 1-0 defeat in Belgium, Bruce highlighted the need to use his full squad as he attempts to balance the prospect of a European campaign with league commitments.
He made nine changes in Lokeren and could do so again when his side host Stoke on Sunday.
"I will look at that because obviously we've got a big game coming up,'' he said. "I haven't got the balance right so far because we got beat but in hindsight I'd still do the same thing because it's vitally important to have enough energy in the team to be right for a Premier League game.''