Chelsea's first-leg draw with Atletico Madrid was marred by injuries to goalkeeper Petr Cech and captain John Terry.
Cech was ruled out for the season with a dislocated shoulder and Terry suffered an ankle injury to rule him out of next Wednesday's second leg at Stamford Bridge.
Jose Mourinho's selection problems are mounting after Frank Lampard and John Obi Mikel were ruled out of the second leg through suspension while Samuel Eto'o and Eden Hazard also struggling with injuries.
"Petr Cech's season over. And John - we have to play the final for him to play with us," Mourinho said.
"We had problems before the game, we had problems during the game, we lost four players during the game, two with injuries, two with yellow cards, but we will fight."
More top news
Leyton Orient have been in free-fall ever since Italian Becchetti bought the club from Barry Hearn in 2014.
A long-awaited report criticises industrial action taken by Aslef and the RMT union over the past year.
The prime minister was shouted at as she left the scene of the tragedy in which at least 79 people died.