Holtby believes that he and his teammates can achieve "something special" this season if they continue to show the kind of determination that they did at Upton Park.
"There is big spirit in the team. When you go out on the pitch you feel that everyone wants to fight for each other – we've built this special dressing room atmosphere," he told the club's official website.
"If you've got that atmosphere like we did [against West Ham] then we can do something special this season.
"The way everyone put their bodies on the line for 90 minutes and fought as a team was great and everyone worked brilliantly as a team. That's the kind of character we need, especially in games like these."
Tottenham are back in action on Thursday when they travel to Cyprus to face AEL Limassol in the Europa League.