DERBY coach John Trewick is calling on officials to be more vigilant when penalties are awarded.

Striker Fabrizio Ravanelli has seen two spot-kicks saved in successive weeks, first by Newcastle's Shay Given and then Liverpool's Jerzy Dudek.

Trewick believes that Ravanelli - who says he will not take another penalty - was let down by the system.

The Italian's failure to convert coincided with Derby losing both games to stay in the relegation zone.

Speaking ahead of tomorrow's duel with Wanderers, Trewick said: "Officials have got to look at these penalty situations more carefully.

"In our last two games the goalkeeper has jumped two-footed off his line, about a yard-and-a-half forward.

"You are not allowed to do that. We all know you can move, but only along the line.

"The goalkeepers have jumped forward to narrow the angle and hurled themselves in the right direction.

"If a goalkeeper does that, he doesn't half narrow the angle down for the kicker.

"We do feel we have suffered two cases of injustice. Referees should be looking in future for this sort of thing."

Ravanelli's replacement penalty kicker has yet to be named although strike partner Malcolm Christie said he would be willing to step up.