Caretaker Blues boss Di Matteo believes his side have not been given the credit they deserve for their remarkable resurgence since he took charge seven weeks ago.
Chelsea were condemned in some quarters for 'parking the bus' in Wednesday night's Champions League semi-final first-leg win over Barcelona.
Arsenal boss Arsene Wenger also questioned their tactics in Saturday's goalless Barclays Premier League draw at the Emirates Stadium, while many have accused the Blues' old guard of not being up to their current punishing fixture schedule.
Di Matteo has managed to bite his tongue over criticism of his side but when it was pointed out that Manchester United had been praised this season for their handling of veteran stars Ryan Giggs and Paul Scholes, the Italian could not help himself.
"Thank you very much. Thank you very much," he said.
"What can I say? From where I'm sitting, we are one point now behind Tottenham, in the final of the FA Cup and semi-final of the Champions League, and we seem to be the worst team in England, you know?
"That's what it feels like sometimes."
Asked if he had used that to motivate his players, he said: "I'm not going to tell you what I use!
"I'm not saying it's unfair. We respect everybody's opinion."
Di Matteo also rubbished suggestions the eight changes he made on Saturday demonstrated he was prepared to sacrifice a top-four spot in the Premier League for the hope of Champions League glory.
"We are not sacrificing everything and I've always tried to select a team that is able to win the games," he said, claiming a failure to finish fourth would be the result of what happened before he took charge.
"The regret is that we've lost many, many points before.
"What we've been doing in the last six weeks, I think the points tally is very good."
Newcastle's win over Stoke left Chelsea four points adrift of fourth place with four games remaining.
Di Matteo said: "We're going to try until the last game and keep going until it's mathematically impossible for us.
"We've a crazy schedule as well, as you all know. So we're just going to keep going and, at the end, we'll see where we stand."
He added: "Our team has played the third game in less than six days. It's crazy.
"It's crazy the demand, physically and mentally on the players. It's enormous. I'm not sure people can actually visualise how much it is.
"It's tough and you could see towards the end some of our players were getting a little bit tired. It's just human."
However, Di Matteo was confident fatigue would not prove fatal for his side in Tuesday's Champions League semi-final second leg.
"The tiredness will be there for all the teams, for both teams, not just for us," he said.
"We have a good squad that allows us to compete and to challenge until the end for these competitions and we are pleased with it.
"These players have been in this position probably many times before and under this kind of pressure and it doesn't really faze them too much."