"We're proud we made it into the last sixteen, but the better team is through to the next round," said Weiss.
"The penalty at the end will lighten the mood a little on the plane home."
Dutch coach Bert van Marwijk named two heroes in their victory.
"Maarten Stekelenburg saved us twice at a very important time," said van Marwijk. "It's obviously fantastic to have Robben come back after injury and show that he's already fit enough to be scoring that kind of goal."