Wanderers have been stunned by an injury setback to Florent Laville's knee that is threatening to keep the Frenchman out until December.

And that has prompted Sam Allardyce to strengthen the centre of his defence by trying to sign two of his impressive trialists.

Laville was thought to be on course for a complete recovery following the operation to repair damage to a cruciate ligament last September, but has now started to suffer some discomfort in the joint."

Now Allardyce is ready to open talks with Julio Cesar, the Brazilian centre back formerly of Real Madrid and available on a free transfer from Real Valladolid, and has also tabled an offer for one of Israel's top defenders,Tal Ben Haim after the manager saw both players in action with Wanderers on their current short tour of Portugal.

"I see Haim as one for the future," Allardyce said of the 22-years-old from Macabbi Tel Aviv, "but Cesar has done so well while he has been with us that he is definitely worth taking a chance on.

"He played alongside Ivan Campo for a while at Real Madrid and was also at Milan, so he has played at a good level.

"Neither deal is in the bag yet, and it will depend on how contract negotiations go whether we can actually get them in. We have to get the ball rolling because we are so short of numbers.

"Even if I get the two of them, I'd still need two more defenders, two more midfielders and a quick striker. And it's not going to be easy finding them at this stage."

While there was good news for Cesar and Haim, Allardyce has told the four other trialists who were with Wanderers in Portugal that they will not be offered deals.

Brazilian midfielder Emerson and Moroccan Hassan Kachloul. plus Lens left-sided defender Cyril Rool, and young Anderlecht striker Sergio McDonald, were released after Wanderers 2-0 defeat.

Allardyce took time out to sympathise with injured Laville: "It's a great shame for Florent. He's had a setback to the original injury and is finding it difficult to stand up to the physical demands of the Premiership.

"It could be a while before he is back in the first team.

"He is working hard but it's important he doesn't rush and we'll make sure that the timing is right before he starts playing again."