Canon Background
https://awoiaf.westeros.org/index.php/Eustace_Hunter

In-Campaign
At the Spring Tourney in 288 AC Eustace sought to make a name for himself by challenging old Darron Brewlan, the knight who had just defeated Mandon Moore. Alas, it was not meant to be. Ser Eustace was skewered on Darron’s opening charge and thusly was eliminated. Ser Darron, perhaps feeling bad for how grievously he wounded Eustace, forewent a ransom and signed his shield (offering a few kind words as well).

In what became known as Ser Jamie’s Tourney in the region, in June of 288 AC, Ser Eustace Hunter won the knife throwing contest and completed in the riding contest and the joust (though he did not fare so well in either of the other events). Eustace faced Ser Darron in the second round of the joust and in a show of chivalry the old knight set the cost of the ransom as two ales. Eustace was the only competitor that day who entered all three contests showing competence or cockiness.