Arsenal and Tottenham have a long-standing rivalry with both clubs situated in north London.
The Gunners had been the stronger of the two teams for the majority of the Premier League era, winning the trophy three times.
Tottenham are yet to win the Premier League but have finished above the Gunners for the past two seasons.
Chelsea, meanwhile, have been a force to be reckoned with in the Premier League since being taken over by Russian billionaire Roman Abramovich.
They have won the Premier League five times, the most recent of which came under Antonio Conte in 2017.
And Pochettino, who is yet to lift a trophy with Tottenham, believes the Blues are bigger rivals for Spurs than Arsenal now.
“It’s a good signal our fans want more every season and with rivalry, always you look at the teams above you,” Pochettino said.
“For us, Chelsea, Arsenal and West Ham have been our biggest rivals. But I think that has changed a bit because of our positions in the table.
“In the last few years Chelsea were always on the top and Arsenal, after 21 or 22 years, were below us again.”
Mauricio Pochettino believes Chelsea are now Tottenham’s closest rivals (Image: GETTY)
Tottenham face Chelsea today (Image: GETTY)
Pochettino has impressed as Tottenham manager since taking over in 2014 but is yet to make a final in any cup competition.
Many believe the former Southampton manager is under pressure to bring silverware to Tottenham.
But Chelsea boss Maurizio Sarri has sympathy for the Argentinian.
Sarri added: “Maybe Pochettino is not in the condition to win at the moment.
“In the Premier League this year there is for sure one team stronger than anyone else – Manchester City. Maybe two, with Liverpool.
Arsenal are traditionally Tottenham’s biggest rivals (Image: GETTY)
“It’s very difficult to win if you’re not the best team.
“Sometimes it’s difficult to win even if you are the best team.
“But it is clear that Pochettino is a very important coach, with or without a trophy.
“For him it’s easier that he has been working with the same team for three or four years. Not easy – but easier.”
Tottenham face Chelsea at Wembley today (5.30pm).