Nottingham Forest's interest in the North-East born midfielder has never waned and they are expected to test Boro's resolve for a final time before the 11pm deadline.
Leadbitter is one of Middlesbrough's most saleable assets and Forest made a number of attempts to land him during the summer. The last offer in August from the City Ground was believed to have been around the £3m mark.
Such an offer now could tempt Middlesbrough – who are also aware of Brighton's interest in Mustapha Carayol - in their bid to bolster their attacking ranks for the final few months of the campaign.
And with the the likes of Celtic and Swansea no longer likely to match Middlesbrough's valuation of Rhys Williams – who suffered a serious Achilles problem on Tuesday night – then Middlesbrough could be tempted by selling in other areas.
But Leadbitter is desperate to stay. Rather than think about leaving, the former Ipswich and Sunderland man wants to focus on staying at the Riverside for the long term and help seal a return to the Premier League.
“There has been speculation in the last couple of transfer windows about me and I have always said from day one that I'm happy at this football club,” said the 28-year-old.
“I have always said I want to stay and that has not changed this time around.
“I will not be nervous building up to the deadline. Football is a strange business, I know that. But I am happy here.
“I love the team, I love playing for this club an I love my team-mates. I want to stay to help this team get out of this league. I want to be here for a few more years yet. I'm enjoying my time here.”
Middlesbrough head coach Aitor Karanka is being kept informed on boardroom progress on transfer targets ahead of tomorrow night.
He suggested after Tuesday's goalless draw that he was still looking for players in a few positions. Recruiting a new striker, however, is the priority.
Middlesbrough hope for positive developments after another performance at the Riverside which highlighted a lack of firepower in the final third.
“We do need to score more goals,” said Leadbitter. “I know we are the third highest scorers in the Championship, but I still think we need more goals from further up the pitch.
“We are all excited ahead of Friday's deadline, we want to strengthen the squad. We know we need to strength if we want to go further. I'm sure the manager is trying his hardest and we need a bit of help.”
Wolves' Kevin Doyle, Norwich's Luciano Becchio, Genk's Jelle Vossen, Sunderland's Danny Graham, on loan at Hull, and Cardiff's Andreas Cornelius are all under consideration, but every deal looks to bring its own difficulties.
Middlesbrough have given themselves a lifeline in recent weeks in the race for a top six place, although Tuesday's draw meant the gap to sixth-placed Reading was widened to seven points ahead of Saturday's trip to Reading.
Leadbitter said: “The last two months have been good. The camaraderie has been good. That's what you need on and off the pitch and we have had that.
“We need that to continue and to build on that. Everyone knows that. Everyone is demanding that from each other in training.
“We can catch the teams above us back up, close that gap again, if we keep that sort of spirit up. The results will come with that.”
The Middlesbrough dressing room are supporting team-mate Williams after his horrible night at the Riverside.
The 25-year-old had to be stretchered off after his Achilles went after an innocuous turn shortly before half-time against Wigan.
The Australian's World Cup hopes are now in serious doubt and he is being assessed to discover the true extent.
Leadbitter said: “It is a really tough time for Rhys. We all wish him well and hope he is OK because it is never nice to see one of your team-mates suffer a serious injury like that. Hopefully he will make a quick recovery.
“We have to carry on what we started with him and try to do it without him now. Another clean sheet against Wigan was a nice platform, but we need to score more goals at the other end.”