AC Milan coach Max Allegri explained the absence of Valter Birsa for their 1-1 draw at Champions League opponents Ajax.
Milan needed a last minute penalty from Balotelli to rescue a point.
"Tonight's approach with a trequartista behind two strikers could be an idea. Until last Sunday we played with two trequartisti, the so-called Christmas Tree formation. Tonight we were solid defensively for 90 minutes, just like against Sampdoria, and that's what we have to build on. The better you defend, the better you can attack," said Allegri.
"We were going to play Birsa this evening, but he had an injury and I put Montolivo behind the strikers, though Robinho is someone who moves around a lot."
