Luka Jovic's goal was enough to dump Inter out of the competition.
"We lacked a bit of everything. We lost balance immediately and made some naïve mistakes for the opener, then got irritable and lost even more balance. It became a very difficult game," Spalletti told Sky Sport Italia.
“If you don't clear your lines first, or make rough passes, everything becomes an open ball to challenge for. If you treat it with more quality, it's within your control.
“We just couldn't keep the ball. I chose Keita and he hadn't played for a while, so was lacking match fitness and that determination you need. I took that risk.
“Even when moving the ball between spaces, we never created anything of note. The early goal just cranked up the tension and made us feel as if there was no chance. We lost it straight away."