Meireles struck in injury-time to edge the second-leg 2-1 in Chelsea's favour.
"It is one of those situations when you think pass the ball, pass the ball, pass the ball - and then you say well done at the end!" admitted Di Matteo having seen the midfielder drill the ball into the net to secure the win.
"So we were pleased and it was a cracking goal that Raul scored. He enjoyed it very much."