Sheffield United boss explains Jack O'Connell decision and free agent transfer chances

O'Connell was a notable absentee from the list of 23 names that United lodged with the league earlier this month, as he continues his battle for fitness after two operations and more than two years out with a knee issue.

Surely on the brink of international honours when at his rampaging best in the top-flight, O'Connell now faces an uncertain future after two years out but is, according to Heckingbottom, "still working hard" in his bid for fitness.

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"Listen, we could put him in at any point," the Blades boss told The Star. "So it's not like the Champions League while you're cutting them off. Like we have a massive squad and we're cutting them out and there's no way they can come back. We've got spare places, you know?

"We've got young players who can come into that and wouldn't count as numbers, we've got Jack who could come into that. And the thing is with us, it was almost irrelevant in the window because we weren't doing anything anyway."

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United were permitted to register as many as 25 players with the EFL, leaving two theoretical spots for O'Connell or a free agent to fill between now and the end of the season. Clubs are permitted to sign free agent players outside transfer windows, but United would have to lift their EFL transfer embargo before they would be permitted to do so.

"We can't do anything at the minute. Zero," Heckingbottom added.

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"If it [the embargo] is sorted, then you never know. If something happened and miraculously we can sign players again and we lost all our centre-backs, then we'd need centre-backs. That's the reason [for leaving two spaces]

"If Jack was fit then he's one of them. If he's not then we need the space. I'm hoping it's irrelevant and we never need anything. But it's just a common sense approach ... just trying to cover as many bases as possible for any what-ifs that may come up."

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