Piet rose to prominence as a lightweight boxer when he challenged Freddie Welsh for the EBU lightweight title. The fight took place at Mountain Ash, [Rhondda Cynon Taf|Mountain Ash] on 23 August 1909. Piet lasted until the twelfth round when his knee gave way and he retired from the fight. Afterwards Welsh stated that Piet was "The classiest boy I met since I came over, he will trim up a lot of fancied boxers if he goes to the States."