WE know boxers expose their bravery every time they climb through the ropes - aware they are putting their lives on the line as well as risking the possibility of a life changing injury.
But it takes a very special kind of courage to swap the gloves for an AK-47 Kalashnikov assault rifle and volunteer to face a superior-armed vicious enemy knowing there's every likelihood you are going to be killed.
Ukrainians Vitali and Wladimir Klitschko, Vasiliy Lomachenko and Oleksandr Usyk - all world champions - have proved they are even more heroic outside the ring as they go to war against the Russian invaders - particularly as they didn't have to.
There have been many famous and unknown boxers who have won gallantry medals on the battlefield for going beyond the call of duty - I have chosen just three of them.
Harry Daniels, who boxed for Great Britain, at the 1920 Antwerp Olympics, never turned pro as he was a career soldier.
In March, 1915 in France, Daniels, a Sgt Major in the 2nd Battalion Rifle Brigade, along with his unit was ordered to advance across acres of No-Man's land.
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They were to storm the German trenches after cutting through the barbed wire. In the face of heavy machine-gun fire and despite being injured Daniels still managed to complete his mission.
Harry was awarded the Victoria Cross. But he still hadn't finished with the Germans. For further acts of bravery on the Western front he also earned the MC.
Daniels one of 13 children and orphaned at the age of six ended up a Lt.
Colonel - In recognition of his outstanding fearlessness a street was named after him in his home town of Wymondham, Norfolk.
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George Carpentier, the handsome debonair French idol was European light-heavyweight champion when World War 1 broke out.
He immediately joined the French Air force and quickly became one of its ace pilots. There's no record of how many German planes he shot down but he must have been something special.
Known as the Orchid Man throughout his boxing career George won the Croix de Guerre and the Medaille Militaire - France's two highest military honours.
When the war ended Carpentier won the world light-heavyweight title and in July, 1921 he challenged Jack Dempsey for his world heavyweight crown.
He was KO'd in the 4th round but the fight in Jersey City made history - it was boxing's first million dollar gate.
Barney Ross, world champion at lightweight, light-welterweight and welterweight enlisted in the US Marine Corps, in April 1942.
Ross, son of a Chicago Rabbi escaped being court martialled for hitting an NCO for making an anti-Semitic remark and instead was sent to the Pacific to fight the Japanese.
During the Battle of Guadalcanal, Ross and three comrades were trapped under enemy fire.
They were all wounded but Ross was the only one able to fight on.
Barney gathered up his comrades rifles and grenades and fought nearly a dozen Japanese soldiers single-handed throughout the night . By sunrise Ross had killed every one of them.
Two of his fellow Marines had died from their injuries and Barney carried the third one - who weighed six stone heavier than him - on his shoulders to safety.
Ross for his incredible exploits received the Silver Star - America's third highest military honour and President Roosevelt gave him a special citation as one of America's greatest celebrity war heroes.
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President John F. Kennedy said "Great crisis produce great men and great deeds of courage".
Words that fit those four Musketeers Vitali, Wladimir, Vasiliy and Oleksandr as snugly as a ten ounce glove.