AC Milan must be angry after Arsenal defeat - Gattuso demands reaction
Milan went down 2-0 at home to the Premier League side in Thursday's last-16 first leg, ending a run of 13 games without a loss in all competitions.
Gattuso's men have a chance to bounce back when they travel to Genoa on Sunday, Milan sitting seventh in the Serie A table.
And the former Italy international demanded a response from his players after Milan flopped to defeat against Arsenal.
"I saw the boys angry, disappointed," Gattuso said. "They were training with lots of grit and desire. We must be angry after a defeat.
"We created 16 chances but had only one shot on goal. We need the killer instinct in the last 15 metres.
"There was lots of enthusiasm, we wanted to score at all costs, 73,000 fans were pushing us, the media favoured us to win... we paid the price for all this dearly.
"But I think this tough defeat will help us to grow. A loss against Arsenal can happen, we could have done better but the important thing is that we put this defeat behind us and we look to the future with enthusiasm.
"First things first. We will focus on the return game after Genoa. We will recover our energies and then prepare for this game."
#Gattuso: "I like working at high intensity, but we have a predisposition to prioritize tactics. It's in our DNA. On the other hand, @GenoaCFC have assertiveness in their DNA and they work extremely hard"#GenoaMilan
— AC Milan (@acmilan) March 10, 2018
Genoa have won three of their last four Serie A games under Davide Ballardini to ease away from the relegation zone.
Gattuso added: "Genoa are doing well with Ballardini, it's not an easy game - it never has been. We have to focus on ourselves and start playing again like we are used to.
"Genoa know what to do. It's going to be a tough one. They don't create a lot but they are very aggressive and ready to win the ball back and play on the counter. We have to be wary of second balls.
"They immediately try to find [Andrey] Galabinov with the midfielders and [Goran] Pandev in support. It's a very important game."