Fightin' Irish is a perk featured in The Saboteur. It is unlocked by knocking out two Nazis. When it is unlocked it is possible to use the Haymaker attack in Nazis. It is the first Brawling perk. The Haymaker is an attack that allows Sean Devlin to use a slightly slower, but much more powerful punch to do much more damage to the enemy than a normal hit. While it's very strong, it takes more winding up which makes Sean more vulnerable while using it.
Game Description: Hold <M> to enter melee, press and hold <F> to charge up a haymaker punch.