If there was ever a time for rumours of David de Gea returning to Manchester United to be made public, the day after his replacement saved the day was probably the worst.

Just 24 hours after Andre Onana saved the day with his heroic penalty save against Copenhagen on Tuesday night, a report claimed that United were prepared to offer De Gea a short-term deal to offer cover in goal.

For what it is worth, club sources have dismissed the suggestion that United would offer the Spaniard another chance at the club after his prolonged exit over the summer.

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United have often deployed such a cautious approach in terms of squad selection. It is the same reason they are so reluctant to let peripheral squad players leave, just in case they might be required, even when it seems so obvious to sell them.

Those feelings might be heightened at the moment, given the recent injury crisis that has seen United limited in defence, particularly at full-back, where they had four of their five senior options all sidelined.

There is still uncertainty over whether Onana could miss as many as nine matches early next year following Cameroon's qualification for the Africa Cup of Nations, with the goalkeeper free to make his own choice on whether he wants to represent his country at such a prestigious event.

United's own selfish perspective is that they would rather have their £47 million man available if possible, though they won't stand in his way if this is something he wants to pursue.

Whatever happens, it certainly raises the question of having a viable back-up option who can actually be trusted to replace Onana whenever he is not available.

United were quick to highlight the impressive experience of Altay Bayindir when he signed for £4.3 million in the summer window, though they haven't backed it up by actually giving him a chance so far.

It seemed obvious Bayindir would make his debut in the Carabao Cup clash with Crystal Palace last month, but Erik ten Hag opted for Onana instead as he looked to acclimatise him to his new surroundings.

"We chose in the League Cup to play Andre [Onana] because he [Bayindir] has to adapt to the England standard. That's why we preferred Andre to play," the United manager said earlier this month.

"But also we have to progress Altay, that's clear. He's made a very good impression in training and he's really developing, so we're really happy with it. We are convinced we have the two right goalkeepers in the squad to do the job for us."

With a much tougher test against Newcastle in the next round of the competition and no obvious dead-rubber Champions League ties on the horizon, it now looks uncertain when the Turkish 'keeper will actually get a chance.

If indeed Onana does get called up for AFCON, then Bayindir could be thrown in at the deep end to replace him, a potential baptism of fire that could end badly for the team.

It still feels like it would be in United's best interests to properly expose the 25-year-old to a first-team match now, just in case he is required to play an extensive run of matches early next year.

That should be the thinking, regardless of whatever happens with Onana. Bayindir was sold the vision of being a backup, but with a chance of playing, it only takes an injury or a suspension for him to be suddenly thrown into the spotlight.

A short-term deal for De Gea, or any other goalkeeper, would totally undermine Bayindir, just as it would undermine the expertise of veteran Tom Heaton as well.

The 37-year-old was oddly one of the standout players during the summer schedule, catching the eye not only with his saves but also with his ability to play out from the back.

Heaton is quite obviously not a player United would expect to be playing every week, but as Jonny Evans has proven this season, veteran status does not mean he should be overlooked or underestimated.

It is understandable to have concerns over replacing Onana; that shows what a special talent they have signed, but any suggestion of re-signing De Gea would be a backwards step when they claimed they had moved on.

United already have two replacements in goal; they just need to trust them.