The League Two strugglers have a lengthy injury list but rookie boss Ainsworth can call on Marvin McCoy, Matt McClure and Danny Foster for the game against the Cobblers.
"Experience counts a lot when you're down the bottom of the league, so it'll be important to get those players back," Ainsworth told the Bucks Free Press.
After being confirmed full-time in the Chairboys job, Ainsworth was happy with his side's display in defeat against Rochdale last week but knows that they will face a tough test against Aidy Boothroyd's men.
Despite the FA Cup defeat on penalties at Bradford, confidence should be high among the Cobblers after their excellent league displays at York and Accrington in recent weeks and with Bayo Akinfenwa in fine form.
"They've got some good players who can play and they have different dimensions to their game," said Ainsworth of the threat posed by Akinfenwa and Clive Platt.
"But ultimately they do like to go up to the big men and play off them."