Chris Long returned to the Cobblers side at Rochdale in midweek, the on-loan Burnley striker was back in the starting line up having recovered from a hamstring injury.
“It helped to have Chris Long back,” said boss Jimmy Floyd Hasselbaink.
“We were always only going to give him 75 minutes on Tuesday because we didn’t want to risk him too much.
“He is getting stronger and we want to get him up to 90 minutes."
Meanwhile, another striker drew praise from the Cobblers boss for his performance in midweek.
“Billy Waters were magnificent at Rochdale and I’m sure he will keep on improving," said Hasselbaink.
Marc Richards (thigh) remains a doubt for Saturday’s game at Gillingham with Matt Crooks (knee), Leon Barnett (achilles) and Aaron Phillips (thigh) all still unavailable for selection.
Lewis McGugan is touch and go after missing the trip to Spotland with a knock picked up in last Saturday’s home game against AFC Wimbledon.
Alex Revell serves the final game of his three-match ban.