a £100 million ($139m) deal at the Etihad Stadium seeing Jack Grealish break the British transfer record, while Romelu Lukaku may be heading back to Stamford Bridge for £98m ($136m). United have also invested, with £73m ($101m) spent on Jadon Sancho and £34m ($47m) on Raphael Varane, but Keane believes more is required in order for the most prestigious of honours to be landed at Old Trafford.