The draw for Champion's League last 16 was entirely redone after a mistake which, according to the UEFA, stemmed from a "technical problem" with the software provided by a third party.
Paris Saint-Germain will play Real Madrid while Liverpool take on Inter Milan in two of the standout ties in the last 16 of the Champions League.
The decision came after an embarrassed UEFA (Union of European Football Associations) was forced to redo Monday's draw following a "technical problem".
PSG had initially been paired together with Manchester United in a tie that would have seen old rivals Lionel Messi and Cristiano Ronaldo come up against one another.
However, the reworked draw sees them play record 13-time European champions Real while the Old Trafford side will face Spanish champions Atletico Madrid.
UEFA had earlier blamed a "material error" due to a "technical problem with the software of an external service provider" as it announced that the draw for the first knockout round would have to be redone three hours later.
Following a technical problem with the software of an external service provider that instructs the officials as to which teams are eligible to play each other, a material error occurred in the draw for the UEFA Champions League Round of 16.— UEFA (@UEFA) December 13, 2021
"Surprising" and "shameful"
With the draw being streamed live from UEFA's headquarters in Nyon, Switzerland, the problem was made evident when Manchester United's name was drawn to face Villarreal.
The two clubs could not have played one another having been in the same group. The ball containing United's name did not then appear to be replaced correctly.
So, they were not included as possible opponents for the next team to come out of the pot. With the whole draw compromised, a red-faced UEFA was left with little choice but to start again.
"It was surprising, shameful and difficult to understand considering millions of viewers were waiting for the draw," Madrid's director of institutional relations, former player Emilio Butragueno, told the club's TV channel.
Round of 16 draw ✔️— UEFA Champions League (@ChampionsLeague) December 13, 2021
Which tie are you most excited for?#UCLdraw | #UCL pic.twitter.com/QvZoT0yxqi
Record 13-time European champions Real are unlikely to be happy with the new draw as they had initially been paired with Benfica in the very first tie before the problems occurred.
A clash with the PSG of Lionel Messi, Neymar and Kylian Mbappe is, on paper, a far tougher tie.
Liverpool face a similar situation. Having initially been drawn against knockout-phase debutants Red Bull Salzburg of Austria, they now face three-time former winners Inter, the Serie A champions and current Italian league leaders.
The mess-up with the draw comes at a bad time for the European game's governing body, at the end of a year in which relations with some of the continent's biggest clubs were soured by the botched attempt at a breakaway 12-team Super League.
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