Despite the Tigers� lowly position on the competition table (11th), the Roosters were unable to match the enthusiasm of their opponents and are now in danger of falling out of the top four.
Missing playmaker Anthony Watts, the defending premiers struggled for cohesion with makeshift halves pairing Scott Porter and Jeremy Gordon.
The Tigers posted first points in the fourth minute via a penalty goal to centre Franco Kmet, which despite the early stage of the match, proved to be the difference between the two sides.
The home side hit the front in the 12th minute when powerful back-rower Michael Burns � by far the side�s best � crashed over. Porter�s conversion extended the Roosters� lead to 6-2.
But the visitors squared the ledger at 6-all ten minutes later through Balmain bench player Rangi Chase � who wreaked havoc with the Roosters� defence all afternoon.
But when Burns� back-row partner Brad Baldry crashed over shortly afterwards, the defending premiers looked to be gaining the upper hand.
That notion was thrown out the window, heartbreakingly one minute from half time, when imposing Tigers winger Samu Wara crossed out wide to tie the game at 10-all. But Kmet�s conversion from the right sideline gave the Tigers a deserved 12-10 lead at the break.
Following on from NSW�s fabled defensive opening during last week�s thrilling opening to State of Origin III, the young Roosters produced a remarkable sequence of defence in the initial stages of the second stanza to keep the plucky visitors at bay.
The Roosters repelled seven sets of six in quick succession, but a spilled ball from speedster Casey Conway with 14 minutes remaining allowed Balmain five-eighth Darren Rodgers to extend the away side�s lead to 18-10.
But despite a second, juggling effort from Burns that reaped a try in the 62nd minute, the Tigers held on to post one of their best wins this year.
For the Roosters, Burns and powerful front-rower Danny Williams were solid up front � but the side will eagerly await Watts� return in the coming weeks as they try to kick-start their finals charge.
BALMAIN TIGERS 18 (Rangi Chase, Samu Wara, Darren Rodgers tries; Franco Kmet 3/4 goals) defeated SYDNEY ROOSTERS 16 (Michael Burns 2, Brad Baldry tries; Scott Porter 2/3 goals) at Aussie Stadium; Saturday, 16th July, 2005; Referee: Peter Betts; Penalties: Roosters 6-4; Scrums: Tigers: 7-6.