That defeat to the Ospreys has put Leinster bottom of the pile after week one of the RaboDirect Pro12 and Schmidt has demanded improvements despite so many high-profile absentees.
"To be honest you have to be pretty ruthless," says Schmidt.
"The reality is the reality. When you perform poorly for 40 minutes and put yourself almost out of the game, people have to understand what that really is."
Leinster have however been boosted by the news that Luke Fitzgerald, who injured his knee against the Ospreys, should be fit to feature against the Dragons.
Waikato captain and tighthead prop Nathan White could also come straight into the starting line-up but back-row Kevin McLaughlin insists that regardless of personnel, last weekend's performance will not wash.
"We're not making excuses, we let ourselves down," said McLaughlin. "We know it's not a case of technique, we just need to be hungrier. I think it has to be a mindset and a bit of a wake-up call."