Argentina winger Di Maria's arrival from Real Madrid for 59.7 million pounds (98.79 million US dollar) on Tuesday took United's spending to more than 130 million pounds in the current transfer window a they try to restructure the playing staff.
Yet there remains a feeling among disgruntled supporters that the club have not done enough in the market to make up for last season's perceived inactivity, with executive vice chairman Woodward becoming a target for criticism.
Having see their team take one point from the opening two matches against unfancied Swansea City and Sunderland, United fans have bombarded phone-ins and forums to bemoan the clear weaknesses in the squad and the desperate need to strengthen.
While Di Maria, the highest assist maker in the Spanish league last season, will add creativity to a frontline that has looked laboured, his signing will not solve the problems in defence and in midfield that have been there for all to see.
United, having parted company with three of the game's most experienced, albeit ageing, defenders in the close season - Nemanja Vidic, Patrice Evra and Rio Ferdinand - currently look bereft of leadership and organisation at the back.
While defenders Marcos Rojo and Luke Shaw have arrived in their stead, neither is likely to fulfil the role of being a commanding figurehead like the players they have replaced.
United also seem to be crying out for a central midfielder who can dominate the heart of the pitch, with the signing of Ander Herrera seen by many as a step in the right direction but not the solution to the team's struggles in that position.
While United's ex-manager David Moyes took the brunt of the blame for last year's woeful seventh-place league finish, paying the penalty with his job, Woodward has not escaped the fans' ire for failing to complete deals for the game's shining lights.
Gareth Bale, Cristiano Ronaldo and Cesc Fabregas were all linked to United last year, but none of them ended up at Old Trafford despite promises from Woodward that the club were capable of spending a world record transfer fee if required.
The signing of Di Maria is certainly a statement of intent by United that shows they remain among the very biggest clubs in the world despite dropping out of the Champions League.
But Woodward, who moved into his post when David Gill stepped down last year, has six days left in the window to show the fans he can deliver the players that manager Louis van Gaal needs to restore United to a place among the game's elite.