There was a cracker in Group D as Inter remarkably fought back from a 3-0 half-time deficit to grab a 3-3 draw away to Benfica.
A much-changed Nerazzurri side knew they were already through before kick-off and played like it, as they were blown away at the start.
Joao Mario scored a hat-trick inside 34 minutes to send Benfica cruising towards their first European win of the season, but Inter battled back after the break as Marko Arnautovic, Davide Frattesi and Alexis Sanchez scored in less than 20 minutes.
Things got worse for the hosts when Antonio Silva was sent off with six minutes to go, but they held on to take their first point of a disappointing Champions League campaign.
Real Sociedad and Red Bull Salzburg played out a 0-0 draw in Spain that leaves the Liga side level with Inter on 11 points.
Those two sides will battle it out for top spot in the group when they meet at San Siro on Tuesday, December 12.
Salzburg are in a strong position to grab the Europa League spot as they sit third with four points, three above Benfica.
