"This was a very difficult game for us, it wasn't the prettiest game but it's all about winning," said Pearson.
"We don't expect to go anywhere and have teams allow us to play. Northampton made it difficult for us but as the game developed we always looked the more likely winners.
"We know what's at stake for us this season and the players are going out every week looking to win games.
"We were disappointing in the first half and we had to work hard to stay in the game. Northampton had some good chances in the first 20 minutes but we gradually got on top in the second half."
The win keeps Leicester 10 points clear at the top of League 1 while Northampton are in the bottom half of the table. 7 points above the drop zone.