Inter head coach Simone Inzaghi lamented his side's failure to "play the perfect match" after their 2-0 Champions League defeat to Bayern Munich.
A first-half goal from Leroy Sane and a Danilo D'Ambrosio own goal were enough for the Bundesliga champions to open their group-stage campaign with three points at San Siro.
The winners of the 2019-20 edition of Europe's premier competition dominated Inter, attempting 21 shots at goal compared to the Italian side's nine as Inzaghi's men only registered two shots on target.
Inzaghi was frustrated with his team's lacklustre performance, telling Sky Sport Italia: "In the first 20 minutes we lost many duels against an intense, extraordinary team, one of the strongest in Europe.
"After the first goal, where we had to do better as a team, we created many potential chances but we missed several last passes unfortunately.
"We brought more pressure in the second half and had opportunities to [get back into it].
"It is clear that you have to play the perfect match against such opponents, we were facing a team of the highest quality, among the best three in Europe in my opinion."
The defeat to Bayern is Inter's second in a row, after they were beaten 3-2 by city rivals Milan at the weekend.
Striker Edin Dzeko knows his team must improve if they are to compete for Serie A and Champions League silverware, telling Mediaset Infinity: "I think Bayern were stronger than us today. It is the truth. Teams like this punish you for every mistake.
"I'm not worried. I know we are strong and we are definitely not 100 per cent yet. These defeats just prove that we have to work."