The Catalans are currently three points off the top six with just four games to go, but Pochettino is aware that Sporting are also desperate for the points as they lie marooned in the relegation zone.
He told a press conference broadcast on the club's website: "Sporting are a team that will come here to run, bite and press us. If we are thinking about other things, we will have problems.
"There is no point in looking back for them, if they want to survive they have to beat us.
"Our objectives have the same importance and the two of us have the same desire to make it happen.
"It is a final for us and if we win our hope remains intact, if we don't our European aspirations will be put back in the garage."
Pochettino is expected to make just the one change from the side that started the 3-1 defeat to Atletico Madrid last weekend, with Christian Gomez coming in for Ndri Romaric.
Sporting kept their slim chances of survival alive with a 2-1 win over Rayo Vallecano last time out, but manager Javier Clemente knows that to make up the six-point gap to Villarreal in 17th they have to keep winning.
He told the club's website: "We have to go there and win and Espanyol know that. They are a young team that have had their up and downs, but not many teams have won there and they are having a great season."
The only change in the Sporting side is expected to come at left-back, where Ayoze Garcia deputised for the suspended Roberto Canella last weekend. With the latter now ruled out through injury, Clemente has suggested he will go with the more defensively minded Pedro Orfila or youngster Alex Menendez to combat Espanyol's strength in the wide areas.