Pochettino, who left Espanyol in November, was claimed to be lining up a move for the struggling La Liga club's midfielder Joan Verdu after taking over from Nigel Adkins at St Mary's.
However, Pochettino, speaking on Spanish radio show Esports Cope, said: “I'm not going to take any players from Espanyol.
"I won't do anything that goes against the club. There are a lot of football players in the world.
"I'm happy they're out of the relegation zone because ultimately I'm just another Espanyol fan.”