It finished AC Milan 2-0 Barcelona at the San Siro, and with the Italians threatening to knock out the Champions League favorites at the last-16 stage.
This was not the result we expected. Barca are running away with La Liga and in dominant form. Milan, meanwhile, are a team searching for a new identity and trying to find their way back to past glories.
What we learned in Milan was that Massimo Allegri's team is a more organised and disciplined unit than we gave them credit for. And also that there is a way to stop this Barcelona team.
There were also lessons learned in the respective performances of Lionel Messi and Stephan El Shaarawy, along with something to bear in mind the next time you study passing stats.
In this clip, B/R's Will Tidey runs down five things we learned.