Fortunately, Lennart Thy has provided it.
The VVV-Venlo striker will miss the club's Eredivisie match with PSV Eindhoven - as well as training - to help a leukaemia patient.
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The German striker, who is on loan with the Dutch club from Werder Bremen, donated his DNA for testing seven years ago in a bid to help a patient diagnosed with leukaemia.
A patient with a close DNA match to Thy has been identified and the 26-year-old has decided to donate blood which could be used by doctors to generate stem cells and in turn possibly generate a cure for leukaemia.
A statement on the club website read: "Of course VVV-Venlo agreed to Lennart's request to co-operate with this very special programme.
The chance of a full DNA match is remarkably small, which is the reason why the situation is so very special.
"Lennart will be absent in Venlo for the whole week and pick up his training after the weekend.
"Lennart considers this a private matter and will therefore not be available for comment to the press.
"On Tuesday March 20th there will be a press moment at VVV-Venlo, where Lennart will answer some questions on this situation.
"This press conference will be the only occasion on which Lennart is available for questions from the media concerning this matter."
Reporting: PA Sport
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