Diego Simeone's side finished top of Group G and have been rewarded with a tie with the seven-time European champions.
However, despite Milan's illustrious history in continental competition, Garcia believes Atletico - who sit joint top of La Liga with Barcelona - have the quality to cause Massimiliano Allegri's struggling side, who are 12th in Serie A, problems.
"It is nice to meet AC Milan and we are raring to go and win," he told the club's official website.
"To do this it will be important to stay true to the style of the team and continue to rely on the football philosophy we have, that will make a good tie.
"Milan are not finding their form, (but) what is not in doubt is that they have great players and can hurt you at any time."
Atletico club director Clemente Villaverde is also excited about the last-16 clash against one of Europe's most successful clubs.
"This isn't just any other team - it's AC Milan," he said.
"They have an incredible history. We respect every team here but we also have potential and will use our strengths."
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