The new season saw a complete overhaul of the playing squad, with Simon Colosimo and former Sunderland and Leeds striker Brian Deane as key signings.
Early results in friendlies against local opposition were not great, but Perth became the first team to defeat Sydney FC, winning 1–0 in the semi-final of the 2005–06 Pre-season Cup before losing in the final 0–1 to the Central Coast Mariners.
Another McMahon recruit, Northern Ireland junior international Neil Teggart, quit the club prior to the start of the regular season.
Originally on a three-game temporary contract, after some impressive performances Mori stayed for the rest of the season and finished with seven goals.
After the Round 20 match against Sydney FC, Alan Vest hinted that the current player group were incapable of achieving anything better and stated that "cliques" had been formed undermining club harmony.