London - Tottenham Hotspur manager Mauricio Pochettino offered a downbeat assessment after centre-back Jan Vertonghen was forced off by injury during Saturday's 4-0 win over West Bromwich Albion.
The Belgium international turned his left ankle as he stretched to keep the ball in play on the left touchline and was in tears as hobbled down the tunnel in the 64th minute.
A ligament injury affecting the same ankle forced Vertonghen out of Euro 2016 last year and Pochettino suggested he could be facing a lengthy lay-off.
"It looks bad for Jan," Pochettino told Sky Sports at White Hart Lane. "We need to wait to assess him on Sunday or Monday. He is very disappointed."
Spurs' win, courtesy of Harry Kane's hat-trick and a Gareth McAuley own goal, was their sixth in a row and took them up to second place in the Premier League table behind leaders Chelsea.
They visit Pep Guardiola's Manchester City next weekend.