Jose Mourinho has confirmed that Son Heung-min was substituted against Newcastle United due to a hamstring injury.
The South Korean was heavily involved in Tottenham's best play in the opening 45 minutes and went close to adding to the four goals he scored at Southampton last weekend as he struck the woodwork twice.
Son didn't appear for the second half and many fans believed that Steven Bergwijn had been brought on at the break to give the player a breather ahead of a big week for the club.
However, his early substitution was actually due to injury and was not a tactical decision.
Asked by football.london in his post-match press conference about Son's substitution, he said : "It's an injury. We'll have him out for a while. It's his hamstring."
Spurs return to action on Tuesday evening against Chelsea, with Maccabi Haifa in the Europa League and a Premier League clash against Manchester United to come after the London derby.
Mourinho does have plenty of options to use in attack but he will have his fingers crossed that Son is back to fitness as soon as possible.
Tottenham's 1-1 draw against Newcastle United leaves the team in eighth after three Premier League games.
