Eric Dier says Tottenham's packed schedule is a danger to player welfare as they face the possibility of nine matches in 21 days.
Spurs are in Bulgaria for the Europa League and could play every Tuesday and Thursday for the next three weeks if they also progress in the Carabao Cup.
"If you look at that schedule, it isn't showing any care for players' physical welfare," Dier said.
Spurs are facing four matches over an eight-day period coming up.
|All or nothing? Spurs' busy run|
|13 September: Tottenham 0-1 Everton||17 September: Lokomotiv Plovdiv (a)|
|20 September: Southampton (a)||22 September: Leyton Orient (a)|
|24 September: Botosani/Shkendija (a) TBC||27 September: Newcastle (h)|
|29 September: Potential Carabao Cup R4||1 October: Potential EL play-off|
|3 October: Man Utd (a)|
After facing Lokomotiv Plovdiv on Thursday, Jose Mourinho's side play Southampton on Sunday, Leyton Orient on Tuesday and then a likely trip to either Macedonia or Romania next week.
"I think there's fantastic depth and fantastic quality throughout the squad and the manager has emphasised that if we want to be successful and win games and go far, it's all about the squad and that squad performing," Dier said.
"But it's common sense really. It doesn't seem like there is any care for players' welfare in that situation."