Arsenal manager Arsene Wenger believes that Andre Villas-Boas needed more time to prove himself at Chelsea.
The Stamford Bridge club parted company with the 34-year-old last Sunday, less than nine months since his appointment, making him the seventh coach to be axed under chairman Roman Abramovich.
The Frenchman believes that Villas-Boas was not given a fair crack of the whip, considering the tough task handed to him.
"When you are not given time, you have no chance," Wenger told Sky Sports News.
"It is sad every time a manager loses his job, because it is a job that demands full commitment. I think he [Villas-Boas] did that.
"I'm sorry that he was not given enough time to do his job."
Arsenal are 9/4 with Bet365 to be leading at both half-time and full-time when they face AC Milan in a crucial Champions League clash on Tuesday.
Chelsea announced the decision to sack Villas-Boas after defeat by West Brom last Saturday extended their dismal run to just one win in seven games in all competitions.
The Gunners boss, speaking ahead of Arsenal's second leg of their Champions League last-16 tie against Milan, offered his sympathy for the Portuguese boss.
"I feel sorry for Andre Villas-Boas, because I know him and I like him as a manager and a man," he added.
"It is sad every time a manager loses his job, because it is a job that demands full commitment. I think he did that.
"Our job is difficult, because we face opinions every day and we need as well the strength to push our own opinion through.
"I am sure that Villas-Boas had the strength to do that."