Spurs missed the chance to move level with fourth-placed Liverpool courtesy of their draw at St Mary's, leaving them facing the possibility of falling five points adrift of the Champions League places should Jurgen Klopp's side beat Swansea City on Monday night.
Tottenham's next three Premier League games will come against Manchester United, Liverpool and Arsenal - with a Champions League tie against Juventus following the North London derby - and Pochettino acknowledged that it is a crucial run of fixtures.
"Of course they will be important for us," Pochettino told reporters at his post-match press conference.
"It is important if we are going to take points and win the games, be sure that we are going to fight and if not, it will be difficult."
Spurs must first take on Newport County in the fourth round of the FA Cup next weekend.