From their first game against Czech side Banik Ostrava to reaching the final in 2006, we’ve picked out 21 iconic pictures from the Teessiders’ European adventure. Scroll down and flick through our picture gallery to look back on some of the most memorable moments.
1. Where it all began
Middlesbrough are drawn against Czech side Baník Ostrava in the qualifying round of the 2004/05 UEFA Cup. Photo: Alex Livesey
2. A debut win
Mark Viduka scores at the Riverside as Boro win 3-0 on the club's debut in a major European competition. Photo: Alex Livesey
3. Lazio beaten at the Riverside
A Boudewijn Zenden double downs Lazio at the Riverside. Photo: Ross Kinnaird
4. Villarreal too strong
The Teessiders suffer their first defeat in the competition after losing 2-0 to Spanish side Villarreal in a group match. Photo: Richard Heathcote