This will be the fifth time the two sides have in the last year, with this being Saints’ fourth trip to the Stadium of Light in that time.
However, it is now more than 11 years since Southampton last beat the Black Cats – something assistant manager Pérez is aiming to change this weekend.
“We know Sunderland very well,” Mauricio Pochettino’s number two told Saints Player
“This will be the fourth time we’ve met them [this season] but, when you are playing a lot of competitions, that’s always a possibility. We are ready to face them.
“We’ve played against them three times, and each single game has been different.
“We have learned from every game against them. We review and analyse every game to determine how we have to improve in case we have to repeat situations.
“For example, we analysed our game against Stoke to prepare better for the game against Hull because sometimes teams defend in the same way.
“We always learn from our games, and hopefully we can play better and more clinically to win against Sunderland.”
The sides met as recently as 18th January, when Saints let slip a two-goal lead on Wearside and left with just a point.
And Pérez insists the nature of that result will not have an effect on the squad’s thinking on Saturday as it looks to secure a place in the last eight of the competition.
“What happened in the last game is finished,” said the Spaniard. “The last game contained one of the best 45-minute [halves] we’ve played so far, and we probably deserved more but sometimes football in England isn’t like that.
“Sometimes one-nil is enough, and sometimes two-nil is a dangerous scoreline but we were very happy with how we played there.
“Now the most important thing is to keep playing in the same style and to keep going with our run of results.
“Hopefully we play a good game on Saturday and stay in [the cup for] the next round.
“If we review the three games we’ve played against them this season, we’ve used different players and different line-ups, but we’ve dominated the three games.
“Hopefully the fourth will be the one we win to go into the next round.”
This will be Southampton’s third game in the space of eight days, with the side having followed up last weekend’s home draw against Stoke City with an impressive victory over Hull City on the road on Tuesday.
Pochettino said earlier this week that he would expect to rotate his squad over the course of the three matches, but Pérez hinted that fans should not expect the level of changes seen in the Capital One Cup and the early rounds of the FA Cup this season.
“The situation has changed,” he explained. “In the first rounds of the cups, we have had different fixtures ahead of us but now we are just thinking game-by-game.
“We’ve played two games in four days, so today and tomorrow we will have to assess how the players are recovering from those two tough matches and decide the best squad for Saturday.
“We have to manage the opportunity [based] on the condition of the players, but we’re always aiming to win games. Now is the time to win, to win and to win so we’re looking to the next round.”