Tottenham players have been warned to improve their fitness or manager Juande Ramos will kick them out of White Hart Lane.
Ramos oversaw his first day of training yesterday and ordered the squad to do a double session, with a light warm-down in the morning followed by an intensive session after lunch.
Alvarez has already told friends in Spain that he feels Spurs players are not in good enough condition to challenge the best teams in the Premier League.
One said: "Marcos has been surprised at their physical condition and feels there is a lot of work to be done to get them in the kind of shape Juande likes.
"I think the players are going to be shocked because they are going to be worked very hard. Anyone who doesn't get in the right condition won't last very long."