Coolaroo made an early statement by winning the pre-season competition so comfortably last month but the Bombers showed they would face some real challenges this season by recording an 11.7 (73) to 8.11 (59) victory in what was an intense and committed round two game.
Souths held a one-goal lead after the first quarter before both teams went into the long break tied on the scoreboard.
The Bombers then kicked five goals to one in the third term to hold a 22-point lead at the final change.
They held off a spirited Coolaroo effort in the final stanza and secured a 14-point win. Chris Grover was strong in a beaten Coolaroo side while Trent Saxelby was influential for the Bombers off the half-back line.
Toowoomba Tigers also recorded their second-straight win of the season on Saturday when they beat Lockyer Valley by 114 points at Gatton Showgrounds.
Luke Adams, Brad Dolley and Josh Andrews each kicked five goals for the defending premiers as they notched a comfortable 23.12 (150) to 5.6 (36) victory over the Demons.
Meanwhile, Highfields came up with a big win over last year's grand finalists Warwick at Roddies Oval.
The Lions scored a 13.9 (87) to 7.8 (50) victory to join Souths, Tigers and University as unbeaten teams this season.
After having the bye in the first round, University got its season off to a solid start by beating Goondiwindi 32.12 (204) to 5.4 (34) at USQ.
University established a 41-point lead after the first quarter and built on that buffer as the game went on, although the heat and lack of match fitness saw the intensity drop off in the final term.
Joel Yosh booted nine goals for the Cougars while Heath Gniel slotted seven.
Last Modified on 12/04/2012 17:18
