Emery and his Aston Villa side will welcome Spurs to Villa Park for a Premier League encounter on Saturday.
Both sides are still in with a shout to secure a place in either the Europa League or Europa Conference League for next season but Champions League football looks beyond them.
Spurs reached the Champions League final in 2019 and were knocked out at the round of 16 stage by AC Milan this season.
Newcastle United have gatecrashed the top four this season while Villa and Brighton and Hove Albion have destabilised the regular top six positions.
“Their expectation in the beginning was to be in the top four,” ex-Arsenal boss Emery said of his former North London neighbours.
“It’s now more difficult than it was five to 10 years ago. There are now seven teams trying to be in the top four.
“Maybe Aston Villa now as well. It’s more difficult.”
Emery added: “Tottenham have had some problems in the last month but they have very good players.
“The last match they played against Palace they kept good balance tactically and they have very powerful players in the transition, being strong defensively.
“They have very good players who can make different tactical decisions.
“The last matches against them at home here, (Villa) have struggled and it’s now a challenge to get a good performance at home.
“We have to believe in our players, in our tactical way we are progressing. That is the match on Saturday.
“To play a great match, spirit and playing and trying to get at them. They have a three-goal difference with us but our mind is to be very competitive and to get better.”
