The U’s boss was at training yesterday, but assistant manager Mickey Lewis took over the routine pre-match media duties.
The club have also not taken the opportunity to rubbish the link, adding fuel to the rumours.
The Oxford Mail understands the managerless Cobblers have requested permission to speak to Wilder.
Many have questioned why the U’s boss would contemplate moving from a side in the play-offs to one which is four points adrift at the bottom of Sky Bet League Two.
Aside from the lack of security with his contract expiring this summer, which was key in his decision to speak with Portsmouth last month, other factors could be influential.
Northampton reached the play-off final last season and chairman David Cardoza has said “significant money” is available to strengthen the squad.
It is in contrast to United, whose only significant business this month has been to replace Asa Hall with Nicky Wroe.
If Wilder was interested, there would still be a sizeable obstacle in the form of United agreeing to a move, which would require compensation.
Chairman Ian Lenagan did allow Wilder contact with Portsmouth, but told the Oxford Mail at the time it did not necessarily mean he would have allowed it to go further.
He said: “When I wrote to Ports-mouth to say they had permission to speak to him, I didn’t in any way imply we would agree he could go.
“You are aware of your own strength and that was another reason I didn’t mind him going and talking to Portsmouth.”
Even though his contract only has a few months left, it is believed United would be eligible for a significant five-figure sum in compensation.
While the uncertainty swirls around the club, the squad have been preparing for this afternoon’s home game against Torquay United.
Lewis admitted it was natural for players to discuss the situation, but felt it would not have an impact on performances.
He said: “I’m sure players are at home talking about it, but when it comes to a Saturday, the game concentrates your mind so much that everything else is pushed aside.
“We are a focused bunch, the players, the staff and the manager.
“When the game finishes I’m sure there will be more speculation. Fortunately there’s another game on Tuesday and we will focus on that.”