The Italian was at the centre of fiery scenes at the San Siro during Tottenham's 1-0 win in the Champions League.
Caught in the middle: Redknapp tries to separate Jordan (left) and Gattuso
Gattuso, 33, headbutted Spurs coach Joe Jordan at the final whistle after a running row during the match.
But the veteran midfielder could have been on the opposite team on Tuesday after Redknapp admitted he tried to sign him in the summer.
Writing in his Sun column, he said: 'I will admit that Gattuso was a player I considered signing last summer. Gattuso was offered to Tottenham by an agent.
Losing the plot: the AC Milan midfielder headbutted Jordan and aimed a punch at the Spurs coach
'I had even managed him before in a big charity game, when I was in charge of a European All Star XI against the Rest of the World one summer.
'Gattuso was fantastic in the dressing room and, because of being his 'manager' on that night against the Rest of the World, I gave it serious thought. But it never quite worked out.
'I have to say that I have met Gattuso before and I thought, at the time, what an absolutely fantastic bloke. A terrific footballer, who appeared very easy to get along with.
Italian job: Gattuso grabbed Jordan around the neck during his side's 1-0 defeat to Tottenham
'He seemed a fantastic character. But on Tuesday night, in front of 80,000 fans at one of the most talked about stadiums in football, he lost it for no apparent reason.'
Redknapp also backed his assistant Jordan who showed restraint despite Gattuso's antics. He added: 'If there is anyone out there who wants a lesson in restraint, they should look at the composure shown by Joe. It was unbelievable.
'Gattuso threw a wobbler, head-butted Joe and the response from him was simply to shake his head in amazement at the flashpoint.
All smiles: Crouch (left) celebrates after scoring the winning goal in the San Siro
'Joe is not about to start throwing punches. He is aware of his position at Tottenham and aware of the responsibilities his position carries.
'Sure, during his days as a player he gave as good as he got - and why not. He wore the AC Milan shirt during his time in Italy with intense pride, giving everything for the club and their fans. No one wants to stand there and be a pushover, do they?
'But I am left shaking my own head wondering what set Gattuso off, what sent him haywire like that. I have never seen anything like it in all my time in the game.'
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Source: Daily Mail
Source: Daily Mail