For every Juninho, Mark Viduka or Grant Leadbitter, there are new arrivals who simply don’t perform, even if supporters thought they would.
Scroll down and flick through the gallery to see the players who were mentioned:
1. (11th) Martin Braithwaite
We saw glimpses of what the Danish international was capable of during his staggered spell at Boro, yet his time on Teesside proved a costly one. After arriving from Toulouse for around £9million, Braithwaite became one of the highest earners at the club but looked disinterested following a public fallout with Tony Pulis. Photo: Nigel Roddis
2. (10th) Michael Reiziger
The Dutch international claimed he turned down Champions League football with Valencia to join Steve McClaren’s Boro in 2004. Yet Reiziger’s spell in the North East never really took off due to a run of injury setbacks. He left the Riverside for PSV Eindhoven a year later. Photo: Richard Heathcote
3. (9th) Didier Digard
Signed from PSG as a 22-year-old at the start of the 2008/09 season, it was thought Digard's physical approach would suit the English game. Yet the holding midfielder missed a large part of the campaign through injury as Boro were relegated from the top flight. The Frenchman left Teesside in 2011 after making just 36 appearances for the club. Photo: Stu Forster
4. (8th) Michael Ricketts
Ricketts averaged more than a goal every three games at Bolton before signing for Boro in January 2003. The striker's spell on Teesside was a nightmare, though, as the one-cap England man registered just 12 league starts and three league goals in 18 months. Photo: Alex Livesey