The Motherwell manager was interviewed for the position in the summer but turned the opportunity down before the Yorkshire club could offer him a contract, with the Bramall Lane side then appointing David Weir.
But Weir, the former Rangers and Everton defender, was sacked last week after winning just two of his 13 games in charge. McCall, who signed a contract extension in the summer to stay at Fir Park until 2015, had emerged as one of the frontrunners to succeed Weir but yesterday made it clear he would give the same response if offered the job this time.
"What do you mean, if?" he joked. "The phone's red hot. No, I'm only kidding. For now, that ship has sailed. It's funny, because a month into the new season, a big new owner comes in and pours money into it.
"The players that they had to sell, they didn't sell. People said to me then, 'do you regret your decision?' No. You make a decision on what you feel is best.
"I didn't regret the decision when they got the money and I don't regret it now because at the moment they're struggling.
"You make a decison and then you get on with it. Now, I'm more than happy at the job I'm doing, I always have been. Sheffield United are a club that mean a lot to me.
"I had some fantastic years there [as a player], so it was a big decision to turn down the job. But once I did it, I was fully focused on the job here. There's a quote I saw the other week: 'find a job you love and you'll never work a day in your life'.
"And I love this, so I don't classify it as work, I classify it as enjoyment, and that's what it has been. I have no regrets either way [about not taking the Sheffield United job]. I didn't have a regret when they ploughed loads of money in and I don't have
a regret now."
Nigel Clough, himself sacked by Derby County earlier this month, is now the outright favourite to take up the vacant position at Bramall Lane.
Motherwell, who are at home
to Hearts today, sit third in the SPFL Premiership, three points behind Inverness Caledonian Thistle, and McCall insisted
there was enough work to do
at Fir Park to keep him happy in the near future.
He said: "I'm not one with a five-year plan that I want to be managing in the Premier League. I'm quite a content person.
That doesn't mean to say I lack ambition but if I'm happy in what I'm doing . . .
"I still feel like there are lots of challenges here, having to rebuild a new team, trying to get to a cup final and trying to keep us in the top six - there are always challenges. It would have to be a really good job for me to leave."
McCall expressed his sympathy for Weir, but acknowledged the former Scotland internationalist's dismissal was a reflection
of the cut-throat nature of the modern game.
"I felt massive disappointment and sadness for him," he said.
"I can't say it was a total shock, because that's how football is, although in my eyes it was far too short a time to judge anybody.
"As managers we all know how unfair it can be. As much as you can go places with a two-year plan, a three-year plan, if you don't produce results early enough in this day and age
a sacking is a probability."