Portuguese Amorim has returned to coaching after being sacked in January by Manchester United and faces a Milan derby against bitter rivals Inter in the Western Australia city of Perth on Wednesday.
Amorim's reign began with a 2-2 draw in a friendly against Celtic in Glasgow last month.
The 41-year-old's immediate target will be a top-four finish in Serie A after AC Milan missed out on the Champions League on the final day of last season.
"I feel that the group is really together," Amorim told reporters in Perth.
"The important thing is to continue with this spirit when things become difficult.
"In this club you need to win every game, so we need to keep that spirit all season."
AC Milan were boosted in the close season by veteran midfield maestro Luka Modric agreeing a one-year contract extension.
Amorim said Modric would play against Inter, having just competed at his fifth World Cup where Croatia were knocked out in the last 32 by Portugal.
"We did a lot to get him back at least for one more year," Amorim said of the former Tottenham and Real Madrid star, who turns 41 in September.
"I'm really pleased with him and he is ready to play some minutes tomorrow."
The match will be an emotional first match for AC Milan since the death of Baresi, who captained the club during a golden era in the 1980s and 1990s.
"When you talk with all the staff about Franco, you see the tears in their eyes," Amorim said.
"Franco was all about the team. The team is the most important thing in our club.
"I will not promise results, but I can promise that I will continue the legacy of Franco."
AC Milan will continue their pre-season against Chelsea in Jakarta on Saturday, while Inter Milan -- who beat Manchester City on penalties in Hong Kong on Saturday -- will remain in Perth to play Juventus on the same day.
Juventus round out the series of all-Italian Perth friendlies against Serie B team Palermo on August 11.
The week-long festival, dubbed "Calcio Italiano", comes after a proposed Serie A match between AC Milan and Como in Perth earlier this year was cancelled because of sanctions imposed by the Asian Football Confederation.
Inter Milan manager Cristian Chivu said he thought hosting a Serie A match in Perth would be a good idea.
"What I suggest is playing it at the start of the season," Chivu said.
"We should start promoting Italian football more, especially in this part of the world."
Calcio Italiano fixtures:
AC Milan will play against Inter Milan at Optus Stadium on Wednesday at 7pm local time.
Inter Milan's game against Juventus will be at 7pm local time on Saturday night.
Juventus' second game in Perth will be against Palermo at 6pm local time on Tuesday August 11.