Son Heung-min played his final game before leaving for the Asian Cup on Sunday as Tottenham suffered a 1-0 defeat to Manchester United at Wembley.
Despite dominating the second half, Spurs' attacking options were not enough to get beyond a phenomenal David de Gea in the United goal.
More worrying than the defeat for Mauricio Pochettino is that while his most in-form player flies off to aid South Korea's bid for Asian Cup glory, talisman Harry Kane was seen nursing an ankle injury at the end of a frustrating game for the centre forward.
"It is worrying because we are going to lose Son to the Asian Cup, and if Harry Kane suffers some issue it is going to be a massive problem.