Tottenham boss Antonio Conte fears Son Heung-min could be unavailable until after the next international break after the South Korea international picked up a muscle injury.
Son - who has made 21 appearances for Spurs in all competitions this season, registering eight goals and three assists - came off after 79 minutes of Wednesday's 2-0 EFL Cup semi-final first leg defeat against Chelsea at Stamford Bridge, but Conte insists that was not because of an injury at the time.
Speaking at a news conference ahead of Sunday's FA Cup third-round tie against League One outfit Morecambe, the former Chelsea and Inter boss said the player felt a pain in his leg the following day and has had a scan to evaluate the damage.
"It was a strange situation," Conte told reporters. "Against Chelsea, I made two substitutions together, with Lucas Moura and then Son. But not for injury, the substitutions, but only to try to give them a bit of rest, 15 minutes of rest.
"Then the day after, he felt a bit of pain in his muscle, in his leg. He had a scan and now we have to make the right evaluation from the doctors. He has an injury.
"I don't know, but probably he will stay without training sessions until the end of this cycle, before the international break."
The next international break is scheduled for the end of this month, meaning that Son would be unable to play for Tottenham again until February.
3 - Son Heung-min has now scored Tottenham's first goal under each of their last three permanent managers (Jose Mourinho, Nuno Espirito Santo and Antonio Conte). Induction. pic.twitter.com/HiSlI2AuAL— OptaJoe (@OptaJoe) November 4, 2021
It will be a big blow to Conte, with Son having created more chances (33) than any other Spurs player this season, ahead of Lucas Moura (27), Harry Kane (21), Sergio Reguilon (20) and Emerson Royal (18).
Conte was also asked about whether there have been discussions about potential incomings in the January transfer window, to which he responded: "The first person who wants to improve the situation is for sure our owner.
"I will have time to speak, also with the people who work within the club to try to understand well the situation, to understand if there is the opportunity to improve this squad in this transfer market. But I think we will do the same thing that all of the teams are doing in these days.
"We have two ways to improve the situation, one is to improve the level of the players that we have in our squad. Another is to implement new players and improve the quality of the squad. But, as you know very well, January is not easy for anyone. So we'll see what happens."