Birmingham boss Steve Bruce has emerged as a strong candidate to succeed Chris Hutchings as manager of Wigan.
Bruce managed Wigan for seven weeks in 2001
The Latics have approached City for permission to speak to Bruce, who is close to marking six years in charge of the St Andrews club.
But the 46-year-old could be out of a job in January should Carson Yeung's proposed takeover of City go through.
Hutchings was axed after 12 games at JJB Stadium, with the team second bottom of the Premier League.
Bruce, who briefly managed Wigan in 2001, held what were described as "positive talks" with Yeung a fortnight ago after the home 3-2 win against the Latics,
He has also enjoyed a close working relationship with Birmingham's co-owners David Gold and David Sullivan, declining the Newcastle job three years ago and then being backed midway through last season when his future looked in doubt because of poor results.
But the uncertainty over whether he has a long-term future at City once Yeung's expected takeover takes place may force him to reluctantly look elsewhere.
Earlier, former boss Paul Jewell told the BBC he rejected an "unbelievable" offer to return to the club.
Jewell, who resigned at the end of the last season after avoiding relegation on the final day, was Whelan's preferred successor to Hutchings.
"He made me an absolutely fantastic offer, an unbelievable offer, but I've had my time there," he told BBC Radio 5 Live.
"I'm ready to come back to work but I'm not for Wigan."
Jewell left the club in the summer, saying he needed a break from football.
I said when we stayed up that I'd taken Wigan as far as I could and I still believe that
Former Wigan boss Paul Jewell
His assistant Hutchings stepped up to replace him but was fired with the team languishing at the foot of the table.
They are currently 19th, with just two league wins in 13 games.
"I was disappointed to see Chris lose his job," said Jewell.
"The chairman called me last Monday to see if I was interested but I said when we stayed up that I'd taken Wigan as far as I could and I still believe that.
"I took them from the third tier to the Premier League and a cup final and I'm proud of that but it was time for Wigan and me to move on."
Graeme Souness and Joe Royle are two names to have been strongly linked with the position.
And Royle on Thursday withdrew his interest in the vacant Leicester manager's post, citing "personal reasons".