Athletic Club scored three times in 16 second-half minutes to recover from a goal down and beat Atalanta 3-2 in Wednesday's thrilling Champions League contest.
Gorka Guruzeta, Nico Serrano and Robert Navarro all found the net for Athletic, who were still a goal down with just under an hour played after Gianluca Scamacca's first-half strike.
Nikola Krstovic scored what proved a consolation for Atalanta, who were as high as third in the live standings at one point but end the penultimate matchday in 13th – level on points with Chelsea in the final automatic last-16 spot – while Athletic are 23rd ahead of facing Sporting CP next week.
An eventful contest at New Balance Arena saw Scamacca outjump Aitor Paredes to head home from Nicola Zalewski's right-sided cross with 16 minutes played.
Lorenzo Bernasconi clipped the post and Unai Simon produced a couple of good saves to deny Scamacca, who also had a goal ruled out for offside, as Atalanta looked good value to add to their lead.
But after more chances fell Atalanta's way, including Charles De Ketelaere finding the frame of the goal, Navarro knocked a long ball into the path of Guruzeta to race in and convert past Marco Carnesecchi.
Serrano completed the comeback shortly after being introduced from the substitutes' bench with a fine first-time finish after being picked out by Navarro.
Navarro added his own name to the scoresheet four minutes later with a crisp finish from the edge of the box, and while Krstovic did tap in with two minutes of normal time to play from an Ademola Lookman knock-down, Athletic were able to hold out for the win.
Data Debrief: Navarro the star as Athletic pick up rare Italian win
Navarro assisted the visitors' first two goals and scored the third himself, making him the first Athletic player to be involved in three-or-more goals in a major European game since Aritz Aduriz against Genk in November 2016.
After digging deep to turn around the game and then hold on, Athletic recorded just their second ever win away to Italian opposition in any European competition, with the other coming against Sampdoria in the 1997-98 UEFA Cup.
Ernesto Valverde's side scored their three goals from three shots on target as they ended with an expected goals (xG) tally of 1.74, compared to 1.99 for Atalanta, who will wonder quite how they failed to come away with anything.