Pompey are still active, with Danny Cowley targeting two more additions to join Hayden Carter, Tyler Walker, Ollie Webber and Denver Hume at Fratton Park.
But the Blues may face competition from the League One rivals, who are also looking to complete deals before February 1,
Here’s the latest transfer news and rumours from the third tier.
Pompey target joins Bolton
Bolton Wanderers completed the signing of Rotherham winger Kieran Sadlier yesterday, as they bolster their squad for a play-off push.
And it appears Ian Evatt has been a long-term admirer of the former West Ham man, after he revealed he failed to land him in the summer.
Sadlier has played 21 games this season for Paul Warne’s side, scoring six goals.
AFC Wimbledon rebuff advances
Sunderland and Barnsley have both been knocked back in their pursuit of AFC Wimbledon midfielder, Jack Rudoni, according to reports.
The Dons’ youth-team product has come of age this term – making 23 league appearances, while scoring seven goals and registering two assists.
And the London club are standing firm over a midfielder they see as playing a vital role in their bid to stay in League One.
Former Blues triallist completes Crewe switch
Another reported Pompey target to complete a transfer this January is Tariq Uwakwe.
The 22-year-old has left Stamford Bridge permanently to join strugglers Crewe, after being continually snubbed by Thomas Tuchel this campaign.
But instead the youngster has joined the Railwaymen in their battle to remain in League One.
Sunderland’s Defoe swoop stalls
Black Cats boss Lee Johnson has revealed there have been no developments in a potential move for Jermain Defoe.
The Sunderland boss told The Sunderland Echo: ‘There's no update on that one. Talks have been going on, but there's nothing to add at the moment.
‘My focus has been on the game the last couple of days. Obviously the deadline for anyone in contract is Monday, but out of contract it goes beyond that.
‘I wouldn’t say we’ve put a deadline on it or anything like that, it’s just got to be right as we’ve said before that.
‘The focus on my side has been training and making the new players feel as comfortable as possible.’
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