This is the last news fans of Tottenham or England wanted to hear, for it not only damages Spurs' chances of silverware but leaves the 24-year-old fighting a battle to be fully fit for England's summer of World Cup action.
The Spurs goal machine missed seven weeks from the same injury in September 2016 and a month again earlier this season, and their medical team believe this incident is similar to the former in severity.
He was injured when his right foot got trapped under Cherries keeper Asmir Begovic.
It means for club he is likely to miss at least four Premier League games, the FA Cup quarter-final with Swansea and a semi-final should they make it that far.
He will then miss the semi-finals if they win and four league fixtures after the global break, a potential top four decider against Chelsea and further clashes with Stoke, Manchester City and Brighton.
Southgate is set to name his next England squad for the friendlies against Holland and Italy at 2pm on Thursday.
He left the ground on crutches and had to postpone a scan due to the amount of swelling.