Tottenham boss Ange Postecoglou confirmed on Thursday that Dejan Kulusevski will miss next week's Europa League final and cast doubt over his chances of being fit for the start of next season.
Spurs' preparations for Wednesday's showpiece with Manchester United in Bilbao were dealt a blow when Kulusevski underwent surgery earlier this week on his right knee.
The Swedish international was forced off early in Sunday's 2-0 defeat to Crystal Palace.
"Disappointing news. Initially we thought it wasn't too serious. The medical team were worried structurally about how the knee was but it blew up the day after and we knew there was an issue there," said Postecoglou.
"He has had surgery and it will put him out for at least a few months.
"I have only got basic information at the moment in terms of recovery, but it will certainly put him out for a while."
Kulusevski's absence is the latest injury blow for Spurs as they aim to end a 17-year trophy drought against fellow Premier League strugglers United.
James Maddison and Lucas Bergvall will also miss the final.
However, there is better news for Postecoglou as captain Son Heung-min steps up his return from a foot injury.
The South Korean had missed seven matches prior to coming on as a substitute against Palace.
Son is set to feature in Friday's Premier League clash at Aston Villa to build up his match fitness before the trip to Spain.
"Sonny will definitely play tomorrow, whether or not we start with him, I'll have a look at," added Postecoglou.
"But he reacted well to playing the other day, no issues with his foot, he's trained well and it makes sense for him to get more match minutes."