Cobblers boss Keith Curle is demanding more from striker Harry Smith after hooking him 45 minutes into Saturday's 2-1 defeat to Macclesfield Town.
The 24-year-old left Macclesfield and joined Northampton for an undisclosed fee earlier in the summer, putting pen to paper a three-year contract at the PTS.
But despite starting all three league games, and coming on in the League Cup at Swansea City in midweek, Smith has struggled to make much of an impression and is yet to score in any of his four appearances.
He had a particularly difficult afternoon against his former club on Saturday, so much so he was withdrawn at half-time and replaced by Vadaine Oliver.
"We need more from Harry," said Curle, who confirmed the decision was tactical rather than injury-related. "He's battling and he's fighting in games to stand his ground.
"He's not getting the protection he needs and sometimes if referee's not going to give him the free-kicks and give us the dominance, then we'll have to bring on a different type of centre-forward."
Oliver, another one of Curle's summer signings, was on for his Cobblers debut against Macclesfield and enjoyed a better time of it than Smith, winning plenty of headers and generally giving the visiting defence more to think about.
The 27-year-old had been made to wait for his first Northampton appearances after injuring his knee in a pre-season friendly at Brackley Town.
"Vadaine came on and I thought he did very well," Curle added. "He won his headers and won his flicks.
"He did a good job but you could tell from some of his movement in the penalty box that there's another yard to come from him."