Manchester United fans have demanded an apology from Italian police over the treatment they received in Rome at the Stadio Olimpico three weeks ago.
Manchester United fans and Italian riot police clashed in Rome
Trouble flared when fans were charged and beaten by riot police trying to control violence.
The demand comes as Greater Manchester Police prepare for United's Champion's League semi-final against AC Milan.
The Independent Manchester United Supporters Association (IMUSA) said those injured should be compensated.
They have threatened to take legal action against Italian police.
IMUSA spokesman Colin Hendrie said: "The authorities in Rome have already admitted too much force was used and confirmation Italian grounds will have stewards instead of police in charge just emphasises something went wrong.
Police charged 16 people following the Rome tie
"Our supporters were struck with batons and sticks for no good reason.
Those who were injured should be compensated financially and there should be a formal apology", he added, "we are prepared to take this matter to court in order to get them."
Violence also flared outside Old Trafford during the second leg of the tie against Roma, with 21 people arrested.
But Greater Manchester Police say they hope trouble will not detract from Tuesday's match against AC Milan.
Officers from Manchester have travelled to Italy to talk to authorities about the two ties and to finalise policing strategy.
Ch Supt Janette McCormick of Greater Manchester Police, said: "We have liaised closely with both clubs in the run up to this game.
"Both clubs are extremely responsible organisations, and I am confident that they know that we all carry a responsibility to ensure the game passes off peacefully."
The teams will meet for the second leg at AC Milan's San Siro stadium on 2 May.