Pochettino's side suffered their first defeat of the season before the international break as the Reds cruised to victory at White Hart Lane.
"I think we have a tough game against Sunderland," he told the club's official website. "They are a difficult team, [and play in a] difficult stadium but most important thing is how we are.
"It's important to be ready and focused in our job, we are still improving under our philosophy, I expect a tough game.
"It has been a difficult two weeks, but we are ready to play, to make a good game. We expect to be better [than against Liverpool] and win the three points."
Saturday's clash at the Stadium of Light kicks off at 3pm.