NORTHAMPTON boss Rob Page is not worried about his side's staying power.

The Cobblers head to Valley Parade tonight sore from the last-minute derby defeat against Peterborough.

It is the third time this season Northampton have conceded a late winner but Page is adamant his team do not run out of steam.

Page, who is considering making changes, said: "I know it's not fitness because they're a fit bunch of lads.

"It's just about switching off and decision-making.

"I talk about being ruthless and that's what I mean, being professional in seeing the game out."

Centre half Zander Diamond is set to miss the game after suffering a nasty injury to his eye socket. Gabriel Zakuani is expected to deputise.

Northampton went an incredible nine months without a league loss until their first defeat since promotion at Chesterfield in mid-September.

But they have lost five of the last eight, including back to back against Gillingham and Peterborough.