The Blues were leading up until the 88th minute thanks to Victor Moses’ headed goal, but Pablo Hernandez’s shot beat Petr Cech from the edge of the penalty box to hand the Swans a point at the death.
“I thought we had a little more of the game and more clear chances than Swansea and when the opposition equalise late on you always feel it is a bit unlucky, but Swansea scored a quality goal,” said Di Matteo.
“We lacked a little creativity. It is hard to win away in the Premier League and this is only the second game we have drawn, the others we have won.
“It was just disappointing that we didn’t hold on to our lead, sometimes when you are not brilliant you can hang on to a result like that.
“At the back we didn’t conceded too much up against their strikers but the one time we did give them space we were punished.”
The result saw Chelsea surrender their lead at the top of the Premier League table after Manchester United beat Arsenal earlier on Saturday.
But Di Matteo refused to read too much into the standings despite his side falling a point behind the Red Devils.
“It is a long season and it is going to be very tight,” he added. “There are going to be a few teams fighting for the top but we are in touch and we are going to show how strong we are in the future.”
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