The Reds had full faith in Lucas who inspired an upset win over the Chiefs playing at No.10 in Cooper's absence earlier in the season - a victory that sparked their six-game winning run leading into the finals clash.
Despite the loss of Cooper, all the smart money was on the Reds after they had won six of their past seven games in Brisbane against the Sharks.
And the Reds were feeding off their remarkable home record of 21 wins in their past 23 games.
But the Sharks had made a habit of crashing the Reds' party.
In 1996, Queensland topped the inaugural Super Rugby table, only to be thrashed 43-25 by the Sharks in the first semi-final at Ballymore.
The Sharks jumped to a 10-0 lead after just 12 minutes thanks to an opening penalty by French veteran No.10 Frederic Michalak before quick hands sent classy winger JP Pietersen down the right sideline.
And it was 17-0 after 23 minutes when fill-in centre Paul Jordaan - a late replacement for ineligible Test centre Frans Steyn - crashed over.
A Harris penalty in the 30th minute finally put the Reds on the board before the wily Michalak blew the deficit back out to 20-3 with another kick.
Reds captain Will Genia combined brilliantly with No.8 Scott Higginbotham to score in the 38th minute.
However, he went from hero to villain when five-eighth Charl McLeod intercepted a pass from the Reds halfback to run away with a 44th-minute try.
Reds openside flanker Liam Gill was controversially denied a 57th-minute try before the home side crashed over on fulltime through Radike Samo following yet another Michalak penalty - but it was too little, too late.
-AAP