AC Milan head coach Massimiliano Allegri put his team's under-par performance down to a lack of preparation time.
The Rossoneri scrambled back from 2-0 down after 22 minutes to a 2-2 draw on home turf in their Serie A opener.
"We hadn't played together in a long while, as the internationals had only just returned, so the squad only managed to prepare for this game yesterday," said Allegri.
"For example, Mark Van Bommel is no longer a young man and only came back from international duty on Wednesday, but he had a good performance. I am also happy with Alberto Aquilani and Antonio Nocerino.
"We could've done better, but we reacted and in the second half created many chances. We won the ball back often, but also allowed too many counter-attacks. Lazio caused us problems and are very strong in attack.
"The fact remains it's no good for us to take such long breaks. We will soon get back in shape," he said.