According to a report in Sky Sports, United had agreed a swap deal in principle with Dybala, however, it was hinging on the Argentine's preference, besides personal terms with the club.
Here's more on the same.
'Juve didn't find an agreement between Dybala and Man United'
Meanwhile, Lukaku instead left United for Inter, where the player's 17 league goals fired his new side to third in Serie A.
"Lukaku is wearing the Inter Milan shirt and not the Juventus one because Juventus didn't end up finding an agreement between Dybala and Manchester United," Lukaku's agent Federico Pastorello told Sky in Italy.
Why did Manchester United move on form Dybala?
United moved on from Juve star Dybala in August 2019 due to his wage demands and excessive requests from his agent. There was a general sense the player would be coming to Old Trafford for the wrong reasons.
Juventus had done an incredible job to try for Lukaku
Meanwhile, Serie A leaders Juve did their best in trying to get the Belgian international.
"Juventus had done an incredible job in trying to get him. They have been the best club for its organization, but also trophies won. Every season it wins something. Lukaku at Juventus would have made many people happy," he also claimed.
Lukaku needed a change of place
"Romelu has a big heart and he needs to be in a place in which he feels loved and people want to have him," Pastorello added.
"From this point of view what made the difference was the warmth of the Inter fans in comparison to the Juventus fans."
Recently, Lukaku claimed that he "didn't have the energy" to stay at United.