New Western Sydney Wanderers coach Markus Babbel has promised his side will work harder and change their mentality after a disastrous 3-0 home loss to local rivals Sydney FC in Saturday's FFA Cup semifinal.

The Wanderers couldn't convert several good chances in the first hour and were made to pay by the more clinical Sky Blues.
Babbel says Sydney's first goal was down to a Wanderers mistake and the third came from a penalty he felt shouldn't have been awarded, but lamented his sides inability to score.

"You learn a lot from a game like this, we have to work harder," Babbel said.

"There has to be a mentality that you win games like this. You want it, you keep going till the goal is coming, don't give up.

"You saw from the tactical side, I think we were better than the opposite side, we had more control over the game. We created many 100 percent goal chances, we couldn't score."

Babbel revealed defender Patrick Ziegler would be out for four weeks after undergoing meniscus surgery.

Playmaker Alex Baumjohann delivered some good set-piece balls, while Babbel was pleased with the efforts of young midfielders Keanu Baccus and Kostandinos Grozos.

Babbel said he was impressed with the occasion with over 14,000 spectators turning out at Penrith's Panthers Stadium.

"I feel very sad especially for our supporters because it was a fantastic atmosphere today," Babbel said.

"I loved it and I hope the crowd saw there was a team on the pitch who were fighting and gave everything."

There were a couple of off-field incidents in the Wanderers supporters area which may attract further scrutiny.

A flare was ignited in the first half and objects, including what appeared to be bottles, were thrown onto the ground in the second half.