Christian Eriksen, Mousa Dembele and Jan Vertonghen were absent from Tottenham training ahead of tomorrow night’s clash with Barcelona at Wembley.
Eriksen has an abdominal injury and Alli a hamstring problem, while Jan Vertonghen (hamstring) and Mousa Dembele (thigh) will also miss out.
Goalkeeper Hugo Lloris is available after recovering from a thigh injury.
Eriksen scored in Tottenham’s 2-1 loss at Inter Milan in their opening group match last month.
Barcelona are top of the group after they began their campaign with a 4-0 home victory over Dutch side PSV Eindhoven, Lionel Messi scoring a record eighth hat-trick in the competition.
Tottenham manager Mauricio Pochettino, who is also without right-back Serge Aurier (thigh), said: “It is a period when we are not having good luck with injuries.
“We are not victims though. We must feel strong. Every player must feel they can win and achieve what we want.
“In the Premier League it is very tough and physical. We had to make a few changes during the Huddersfield game but football is about the squad.
“We need to make sure every player feels important.”
Harry Winks and Victor Wanyama, who came on at half-time during the 2-0 win over the Terriers, could start against Barcelona.