Lucas Biglia was surprised the VAR was not used to review a clash between himself and Radja Nainggolan during the Milan derby.
Biglia was booked for a tackle on Nainggolan in the first half of Sunday's Serie A clash, which Mauro Icardi settled with a late header.
But replays indicated Nainggolan was perhaps fortunate not to be punished as he caught Biglia heavily in the incident.
Nainggolan was subsequently replaced by Borja Valero with Luciano Spalletti indicating the midfielder could be out for "a while" after damaging his ankle.
The former Roma midfielder is therefore unlikely to be fit to face Barcelona in the Champions League on Wednesday.