The central defender, scheduled to be out of action until Christmas after rupturing an Achilles tendon in March, was a shock addition to training yesterday.

"It is absolutely fantastic news," said manager Alan Irvine. "Liam is way ahead of schedule and we are delighted to see him taking part again."

Chilvers completed the full session at North End's Springfields training base.

The 26-year-old still faces weeks of hard work to get up to match fitness – but he could be back playing by October.

Irvine said: "Obviously he is a considerable way behind everyone else, but it was still great to see him out there with the lads.

"He was able to do the full session and then did a running session in the afternoon.

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"Obviously he was delighted to be out there. He knows he is way off the pace at this moment, but it is still a massive bonus.

"I have to say it is very unexpected. There is no way I thought Liam would be training with us in August.

"He deserves a lot of credit for reaching this stage so early. But it is also full credit to the surgeon and our physio staff."

While Irvine was celebrating the return of Chilvers today, he was also coming to terms with the probable loss of full-back Callum Davidson, at least for tomorrow's trip to Sheffield Wednesday.

The Scot, who missed out on the midweek international against Northern Ireland with a knee injury, is not expected to make Hillsborough, but could return to face Derby County in Tuesday's Carling Cup second-round tie at Deepdale.

Chris Brown remains on the casualty list with sciatica. But, long-term injuries apart, those two are likely to be the only absentees from the squad.

Irvine said: "Callum has got to be a big doubt. We haven't given up completely on him being fit, but it doesn't look likely.

"If he doesn't make it for this one, then hopefully he will be okay for the cup game."

PNE cross the Pennines looking to make it four wins out of four. But they also want to exorcise the ghosts of last term's trip to Hillsborough, a game which proved the low point of the season.

Losing 2-1 on New Year's Day dumped them at the foot of the table. But it also proved to be a turning point with Irvine mounting a spectacular salvage operation.

After now, after beating Ipswich and Crystal Palace in the league and brushing away Chesterfield in the Carling Cup, Preston have had their best start to a season since 1999.

Irvine added: "We are hoping we can build on what we have done so far.

"But Sheffield Wednesday is another hard game. Everyone knows how difficult it is to get a result at Hillsborough.

"They have had some injury problems and we are not sure how they will line up.

"So we certainly have to be prepared for any eventuality."

Wednesday lost right-back Richard Hinds with a broken ankle at Wolves last weekend and have signed Middlesbrough youngster Tony McMahon on a month's loan to replace him.

The 22-year-old, who spent time on loan at Blackpool last season, goes straight into the side tomorrow.