Bolton have made an official protest to Uefa about the treatment of their fans by Spanish police during last night's Uefa Cup tie against Atletico Madrid.

The English club reached the last 16 with a 0-0 draw in the Vicente Calderon stadium, having won the first leg 1-0, but said the triumph was marred by skirmishes between Bolton fans and baton-wielding Spanish police.

The club's website said fans had been subjected to unprovoked baton charges and over-aggressive use of police horses outside the stadium.

"I have great sympathy for any of our supporters who have been injured by what is clearly an overreaction by the Spanish police," Bolton chairman Phil Gartside said in a statement issued on Friday. "The club will be pursuing the matter at the highest level and seeking an explanation from the Spanish authorities."