Sunderland face strong competition from Bolton Wanderers for summer target Charlie Wyke.
The striker has a year left on his Bradford City contract and the Black Cats have already seen one bid of £600,000 turned down.
Reports over the weekend said Sunderland had gone back in with an improved offer, which could be worth as much as £1million, though Bradford sources at Valley Parade have told the Telegraph & Argus that is "pure speculation".
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Wyke is one of Jack Ross' main summer targets but he is also on the wanted list of Bolton chief Phil Parkinson, who wants Bolton chairman Ken Anderson to seal the deal.
Bolton have the advantage of playing in the Championship but Middlesbrough-born Wyke is understood to be open to a move to Wearside as Sunderland look to secure promotion from League One at the first time of asking.
Speaking at the weekend, Ross told the Echo: "Wyke is ongoing, he’s injured at the moment anyway. Stewart [Donald] to be fair to him, is very, very eager to bring players in and he gets a bit impatient with it but we’ll be fine, we’ll be alright.
"I would think so [signings before Middlesbrough], but time does run away from you. I’d be very hopeful of getting some reinforcements before Boro.
"I’m very conscious of getting the right ones, we could have signed bodies before now but it would have been for the sake of it. Hopefully we’ll have more bodies in before the Middlesbrough game."
Wyke is currently out with a knee injury picked up in the friendly against Sheffield United.
Bradford head coach Michael Collins said: “Charlie picked up a niggle the other day but at this moment I leave it to the medical department. He’s being assessed on a daily basis.
“He is a very big asset for the club and when they tell me he’s fit, he’ll come back into the fold. It’s as simple as that.”
Bolton boss Parkinson said: "The key area is the top of the pitch. We need more strength.
“Ken (Anderson) is waiting to hear back from one or two chairmen and we need to make progress in that area.
“At the start of the summer we gave the chairman a list of strikers that we thought were realistic and he asked me which one was at the very top of that list.
“I don’t want to discuss the name – I’m sure it’s documented – but we’re going for that one.”