These two signings, should they come off, would be such a huge boost to a club already on the up because of Louis van Gaal's arrival.
The arrival of arguably the Bundesliga's best central defender and arguably Serie A's best box-to-box midfielder would be the long overdue addition of world class stars to key positions in the team.
Those two international players, alongside fellow new signing Ander Herrera, David de Gea, Juan Mata, Wayne Rooney and Robin van Persie, would create a hugely strong spine to the team that may be comparable to any other side in the division.
Vidal is the subject of a rumoured club record £47 million bid, with various sources implying a transfer is on the cards, though others stating the Chilean is happy to stay in Turin.
Likewise, Hummels is still being linked to Old Trafford despite Dortmund ruling out a bid.
The next few days will indicate how likely any transfers are.
In a perfect world, United would bring in another centre back as well as a top class defensive midfielder, but there are still players at the club capable of finding their feet under the former Netherlands manager.
Van Gaal proved while in charge of his country in the lead up to the World Cup, that he had plenty of young individuals yet to reach their potential that he could convince were capable of becoming world beaters.
The 62-year-old's approach could revitalise the talents of the likes of Phil Jones, Rafael, and even someone like Tom Cleverley, so easily derided by the English media.
Do you agree that United could challenge for the league again if they sign Vidal and Hummels?