The European Champions have lost their past three pre-season friendlies, including a shock 3-1 defeat by Championship side Brighton on Saturday.
London Olympic commitments for striker Daniel Sturridge, midfielder Juan Mata and new Brazilian signing Oscar have given Di Matteo little time to mould his squad for the upcoming season.
The Italian was also been forced to wait for those who took part in Euro 2012 to return from extended holidays including England defenders John Terry and Ashley Cole.
But their were no excuses for Chelsea as they were comprehensively beaten by Brighton with Fernando Torres and Belgian playmaker Eden Hazard both playing in a near full-strength side.
"We haven't had the whole team together yet," Di Matteo told the club's website.
"Some players have only been back nine days, some 16, some 21 and some are not back at all, but when they are back we can all work together.
"I was expecting more from my team in terms of urgency and movement. I was looking for a better performance than the one we gave today [Saturday].
"We were too stretched, never aggressive enough and didn't get the ball back quickly enough when we lost it.
"With the ball, there wasn't enough movement and there were a lot of things we didn't do. We have to be a bit more focused and sharper."
Di Matteo added that it would take time for Hazard to adapt to life in the Premier League but he is prepared to let the 21-year-old settle following his transfer from French club Lille.
"Hazard played on the left, we want him to be incisive, he had good spells but we need to be patient," he said.
"He's a young man coming from a different league and it takes time to adapt."
Chelsea are due to play Premier League champions Manchester City in the Community Shield next Sunday and will have everyone except Oscar, who is through to the semi-finals of the Olympic tournament with Brazil, at their disposal.
