Kane limped off the pitch after a challenge with England teammate Fabian Delph during Tuesday’s Champions League quarter-final first-leg win over Manchester City at the Tottenham Hotspur Stadium.
It immediately looked serious as Kane was unable to put any weight on his left foot and was helped down the tunnel, later leaving the ground on crutches and with the joint in a brace.
The club’s medical staff will allow any swelling around the joint to subside before a scan to reveal how bad the injury is.
Pochettino admitted that the injury could end the England captain’s season, which would be a huge blow to the club’s hopes of Champions League progression and also qualification for next year, with Spurs still locked in a top-four battle.
England boss Gareth Southgate will also be concerned, with the Nations League Finals looming in June.
“It’s very, very sad. It’s going to be tough and we’re going to miss him — maybe for the rest of the season,” Tottenham’s Argentine coach told BT Sport.
Kane, who injured ligaments in his left ankle during Tottenham’s Premier League defeat against Manchester United on January 13, only returned in late February, after missing seven matches.
The 25-year-old, the winner of the Golden Boot at last year’s World Cup, has suffered five ankle injuries in just two-and-a-half years.
Tottenham’s talisman appears susceptible to ligament damage whenever he rolls or impacts his ankle in a challenge.
He has an impressive recovery rate but Pochettino will have to prepare to be without his top-scorer for the remainder of the season.
Spurs will look to Son Heung-min to step into the spotlight as the South Korean promptly did against City, hitting the winner after Kane went off in the 1-0 victory.
Son took centre stage during Kane’s last absence, scoring four goals in four games, while Fernando Llorente is likely to get a run-out against already-relegated Huddersfield on Saturday.
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