At 3.45pm on Monday I had left him cheerfully contemplating United's FA Cup quarter-final at Coventry City this weekend. He was not blissfully content, but, if anything, he appeared to be more resigned to the difficulties of being manager at Bramall Lane than inclined to offer his resignation.
"When will the article appear?" he asked as we parted. "Could you send me a copy?" Earlier he had been laughing with his assistants, Russell Slade and Steve Thompson. These were not the comments and actions of a man anxiously wrestling with a difficult choice. He was excited about being fifth in the First Division and at the tantalising proximity of Wembley. The mood change came later that evening.
It is more difficult to understand the timing than to discern the reasons why. Brian Deane, Jan Age Fjortoft, Carl Tiler, Mitch Ward and, last week, Don Hutchison had been sold and he was operating on a player's contract because the club was haggling over his managerial terms. Losing his coach, Willie Donachie, to Manchester City last week must have pushed him closer to the last straw.
It sounds like a recipe for chaos, I had said to him, pointing out that there would have been shareholders with violent intent if a major public company (Sheffield United are listed on the London stock market) such as ICI operated in such an unconventional manner. He smiled, thought carefully, and replied: "Those are your words not mine."
"That's football," he continued after a another pause. "There's always something that makes you look up in surprise. It's opened my eyes being in this seat, watching the ups and downs, the comings and goings. They are things you have to cope with as a manager, the sort of things as a player you wouldn't dream were being done. It's not just a case of picking the team and coaching, it's all the other things.
"I've got agents phoning 24 hours a day, faxes coming in, TV crews and reporters to deal with. It's nice when you're doing well, so I hope it will continue because things can turn round quickly in football."
Spackman will have a greater understanding of that last sentence this morning. He became manager ahead of his own timescale and voluntarily reduced to the ranks of a player again after nine months of success dredged from an unpromising, not to say nearly impossible, position. How he can be expected to train and perform for his successor is a dilemma the new man will not enjoy tackling.
A clever midfield player with Bournemouth, Chelsea, Liverpool, Queen's Park Rangers and Glasgow Rangers, who would have won England caps but for a series of untimely injuries, Spackman was pointed towards Bramall Lane by an 18-month lay-off. He expected to serve an apprenticeship as Howard Kendall's playing assistant until the managerial sorcerer left for Everton last summer.
"I thought if I came in with Howard and spent two or three years with him he might decide to move upstairs or do something else. I thought then I'd get my chance, but it came at least 12 months earlier than I anticipated. I decided that if I was a a failure then at least I'd given it a try. I wouldn't be thinking `if only' in five, 10 years' time."
Some failure. The Blades did not suffer their first defeat until Walsall beat them in the Coca-Cola Cup third round and it was 25 October before their first League reverse. Even with players disappearing like a magician's rabbits - Deane with 13 goals and Fjortoft 12 are still the Blades' top scorers - they maintained an unbeaten home record that was extended to 24 games on Saturday.
"It just shows the character of the players we have got here really," Spackman said. "Things were going very well at the start but the team began changing because of injuries to Dane Whitehouse, Wayne Quinn and Paul McGrath and then there were the transfers. It feels like people have been coming and going all season. You get to a point where it becomes normality and you have to get on with it."
How many players had left against his wishes? "I can't really say," he replied. "That's a political matter, isn't it? Obviously, to lose your two top scorers on the same day - 15 January - wasn't the best thing that could happen, but all credit to the other lads who went out the following Saturday and beat Wolverhampton Wanderers 1-0, playing some very good football. That was a tribute to the spirit here and their ability."
That spirit, rather than their ability you suspect, will be under duress on Saturday when United will be expected to rise from the rubble of domestic strife to tackle Coventry of the Premiership. They were underdogs before Spackman's departure; now they could be barking and biting without a lead.
"We would have preferred a home draw," Spackman said, "but we've nothing to lose. The pressure's on Coventry, who are expected to win. That's the romance of the Cup. You know anyone can get to the final. While you're still in you've got a chance."
Sadly, Spackman will only be "in" if he plays for Sheffield United again this season, but that can be safely consigned to the pigs might fly category. A manager's job elsewhere will surely be offered soon.