PHOTOS: Think Valencia's eye was bad? Check these boxing injuries…

After just seven minutes of Manchester United's clash with Olympiacos, Antonio Valencia required medical attention…

Antonio Valencia was left with an abnormal eye swelling after a coming together of heads with Arsenal's on loan star at Olympiacos; Joel Campbell, six minutes into their Champions League match-up at Old Trafford.

Valencia received immediate treatment but went on to continue participating in what must be considered a testament to his toughness, aiding his team's push for a 3-0 win and consequent progression into the quarterfinals.

While bruising of such grotesque proportions is unique in football, it is an occupational hazard in other sports - particularly boxing - and such injuries can occur in nationally-televised fights, such as the 2011 slobberknocker between Pawel Wolak and Delvin Rodriguez, a contender for Fight of the Year.

At the Roseland Ballroom in New York, a middleweight attraction headlined the ESPN bill and the two 160-pounders went to war, earning a majority draw and a lucrative rematch later in the year.

The photograph below is an evidence of the damage Wolak sustained in the rock-em, sock-em dust-up.

What perhaps makes matters worse is what happens when a swelling like that occurs… Wolak was later submitted to hospital, underwent a CAT scan where no broken bones were revealed but he did suffer a hematoma, however, that did not stop his opponent Rodriguez from targeting the swelling as the Dominican sought to "pop" the swelling.

Valencia is probably thankful no Olympiacos player intended on making his swelling worse by kicking him in the face!

There have been worse swellings than even Wolak's, though, as Russian cruiserweight Denis Lebedev was brutalised by Guillermo Jones in May, last year, where Jones was so powerful and accurate that he sealed Lebedev's right eye shut, hospitalising him for five days after the bout.

Check out the picture below. Want to know the worrying thing? Lebedev is not even put off and he and Jones are due to trade heavy leather once again next month! A rematch has been scheduled for the Dynamo Palace of Sports in Moscow, April 25, in a fight which has the WBA cruiserweight title on the line.

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