United are 13th in the table going into Sunday's Manchester derby and Ruben acknowledged that the club and team are going through a period of short-term change, in the pursuit of long-term improvement.
Our head coach added that, while it might be 'crazy' to believe we will challenge for the title next season, it is not in his nature to think it will take years for the Reds to compete in the Premier League again.
He also suggested that 'one or two big players' could be added to the squad this summer as we seek to narrow the gap.