The Owls take a 2-0 advantage into the rematch with Brighton.
Goals from Ross Wallace and Kieran Lee ensured that Carlos Carvalhal's men put one foot in the final after the first leg. But the centre-back is adamant that sitting in and hoping to keep the Seagulls out would be the wrong strategy for Monday's rematch.
"We can't allow Brighton to stamp their authority on the game. It will be a long 90 minutes if we try and defend," he told the Star.
"We can't afford to sit back as 2-0 is a dangerous scoreline. We can't get carried away thinking we have done all the work. It's only half-time."
The Owls will certainly be wary of the fact that going to the Amex Stadium and setting up to hold onto their lead could land them in serious trouble if Brighton bag an early goal as the transition back to their more natural style of play could prove difficult.
And with Chris Hughton's men finishing the regular season in third place, it is clear that they have the quality to punish Wednesday if they allow the home side to take the initiative and get onto the front foot.
But if the Owls can pick up where they left off and perhaps bag an early goal, it would be a huge blow to Brighton's chances of turning the game around, and may then allow the away team to adopt a more defensive mentality to ensure that the door is fully closed on a comeback.