Tottenham have been dealt a blow to their hopes of reaching the Europa League semi-finals ahead of their game away at Eintracht Frankfurt.
Ange Postecoglou revealed that captain Son Heung-min has not travelled for Thursday's last-eight second leg.
Spurs were held to a 1-1 draw last week at home, a game in which Son started and played 79 minutes before being hooked for Pape Sarr.
Winning the Europa League would spell the end of Tottenham's 17-year trophy drought, having last won the EFL Cup in 2008.
But Postecoglou's hopes of bringing silverware back to N17 have taken an unfortunate set-back.
He said on Wednesday: 'Sonny didn't travel in the end. He's the only one who misses out. He trained yesterday but didn't feel right.
'We've left him out and rest is the best way of recovery. It is only Sonny that misses out.'
Son has made 41 appearances for Spurs this season, scoring 11 goals and providing 10 assists in those games.
In the Europa League, the South Korean is their joint-top scorer (three goals) alongside Brennan Johnson.
As well as Son, Radu Dragusin is, of course, absent for the visitors as he recovers from an ACL injury he suffered in February.
Meanwhile, Kevin Danso is not expected to return until next Monday at the earliest, when Spurs host Nottingham Forest in the Premier League.
If Spurs progress against Frankfurt, they would face either Bodo/Glimt or Lazio in the Europa League semi-finals.
Glory in the competition would end a three-year absence in the Champions League for Tottenham, as it would secure them automatic qualification to Europe's biggest club contest in 2025-26.