Cobblers defender Ben Tozer will miss the next four to six weeks with a knee injury.
Tozer was not in the matchday squad for last Saturday’s game against York City and had his keen scanned on Monday.
The results of that scan have shown damage to the meniscus, the diagnosis for which may require a minor operation, although rest may be the preferred option.
The blow is a significant one for Northampton as Tozer can play at centre-back and is the only cover for right-back Brendan Moloney, but the impact of his loss is lessened by the return to training of Zander Diamond, after a hamstring pull, and Lewis Hornby, who has had a dead leg.
“It’s a bit of a blow to us because Ben covers a few positions and it’s disappointing for him and for us,” he said.
“On the plus side, Zander Diamond is coming on really well and hopefully he’ll be available for selection on Saturday, as will Lewis Hornby, who is back in training this week.”