Harry Kane will be out until April at the earliest, his club Tottenham Hotspur have confirmed.
The striker sustained a hamstring injury in Spurs' 1-0 defeat away to Southampton on New Year's Day.
Kane suffered a ruptured tendon in his left hamstring and requires further surgery.
Spurs' expectation is that Kane will return to training in April.
It means Kane will miss both legs of his club's Champions League last-16 tie with RB Leipzig. Should Spurs progress, he'd be in a race against time to be fit in time for the quarter finals which begin on April 7 and 8.
Kane will miss at least 10 Premier League games while he's recuperating. They include this weekend's visit of Liverpool, February games with Manchester City and Chelsea, and a home game with Manchester United on March 14.
With Mourinho reluctant to plunge Republic of Ireland teenager Troy Parrott into first-team action, it's likely Spurs could dip into the January sales in order to solve their paucity of options up front.
Spurs have been linked with AC Milan frontman Krzysztof Piatek.
The Poland international centre-forward only joined the Rossoneri in January of 2019, but he's scored only 4-times in 18 Serie A appearances this season.
If Milan are to do business, it's believed they want to recoup as much of the €38million they paid to Genoa for Piatek's services last year.