The 23-year-old suffered a torn hamstring in last week's derby defeat to former club Burnley and will be sidelined for four weeks.

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It's a big blow to North End who have missed his influence in the engine room, with their form taking a dip with him out of the team.

Chaplow first injured his hamstring in the goalless draw at Coventry last month, missing the following two matches – the win over Nottingham
Forest and Wolves' 3-1 victory at Deepdale.

He returned among the substitutes at Turf Moor last week, but within
minutes of being summoned from the bench to replace Darren Carter, he damaged the muscle again.

It sidelined him for Tuesday's loss to Swansea, and it looks like being the end of the month at the earliest before he's back.

One small consolation for PNE is that the fortnight's international break begins after today's visit to Watford.

Manager Alan Irvine said: "It's really unfortunate – the injury was another thing which went against us at Burnley last week.

"The very first run Richard made, he felt his hamstring tighten up.

"Having made all our substitutions it meant we couldn't do anything about it.

"Richard had to play on for the remainder of the game without being fully able to contribute.

"With hamstrings, no matter what you say, there is no truer test of them than a game.

Meanwhile, Liam Chilvers (right) continued his comeback from a snapped Achilles tendon by playing an hour in the reserves' 1-1 draw at Morecambe in midweek.

And Irvine revealed the centre-half has stepped up to the next stage of his rehabilitation period after seven months on the sidelines.

He said: "Liam resumed training again on Monday after a little hamstring pull, and I'm delighted about that.

"The thing that he is looking for now is that explosive power which you need in games.

"When you are recovering from a long-term injury, you generally have to put in the mileage to get yourself back to fitness.

"Then the final bit is the sharpness, so Liam is on a speed programme at the moment.

"It's about quality, power and speed rather than distance now. It's the last piece of the jigsaw."