Former Liverpool managing director Christian Purslow has described Alexis Sanchez's January transfer situation as "a once in a generation opportunity".
The Chile striker's contract at Arsenal was due to expire at the end of the season, leaving the January window as the last opportunity for the Gunners to cash in on their player.
Sanchez was widely rumoured to be heading to Manchester City, where he would have worked under Pep Guardiola, his former manager at Barcelona.
However, the Citizens pulled out of the deal as they could not meet the 29-year-old's wage demands, allowing Manchester United to swoop in and sign the player in exchange for Henrikh Mkhitaryan.
Chelsea also reportedly emerged as suitors for Sanchez, leaving Purslow to describe the sequence of events and ensuing "little auction" as Arsenal's "dreams come true".
When asked whether anyone in the game saw anything other than a Sanchez move to City before the window opened, Purslow told Sky Sports News: "I don't think they did. I think everyone thought that was a done deal.
"We will never quite know the sequence of events that led to that potential transaction winding away into a United purchase. It has the look from the outside, I don't know this to be true, that Arsenal out of nowhere had their dreams come true.
"Rather than being in a unilateral discussion with City taking their best player nearly on a free they had a little auction going when Jose Mourinho and Antonio Conte both spoke up in early January that actually getting Sanchez was a once in a generation opportunity to buy a top player for not much money down."
Sanchez has made two appearances so far for United, registering one assist.