The Black Cats are building towards the start of their Championship season on August 10, while Eldense will open they Segunda Division campaign on August 19.
Match preview
At the time of writing, Sunderland have played two pre-season fixtures, with both of those matches taking place last Saturday, beating South Shields 5-0 before suffering a 2-1 defeat to Gateshead in a double-header.
The Black Cats will also be in action on Friday night against Nottingham Forest, though, before returning to action with a clash against Spanish outfit Eldense on Sunday afternoon.
Sunderland's 2024-25 Championship campaign will begin on August 10 against Cardiff City, and after this weekend, they will have just three pre-season games remaining, tacking Blackpool, Bradford City and Marseille.
Regis Le Bris is now in charge at the Stadium of Light, with the 48-year-old arriving at the end of last month, and he will be bidding to improve on Sunderland's 16th-placed finish in the Championship last term.
The Black Cats have only made two signings during the summer market, with Alan Browne and Simon Moore arriving on free transfers, while five players have departed on free transfers.
Eldense, meanwhile, have not been in action since ending their 2023-24 Segunda Division campaign with a 1-0 home defeat to Sporting Gijon at the start of June.
Deportivo will therefore kickoff their preparations for the new season against Sunderland on Sunday, before tacking Real Oviedo and FC Cartagena before the end of the month.
Dani Ponz's side will then take on Tenerife and Villarreal II at the start of August, before opening their 2024-25 Segunda Division campaign against Tenerife on August 19.
Azulgranas finished 16th in Spain's second tier last season, and they have never operated in the top flight, spending the majority of their history in the Tercera Division, which is the fourth tier of Spain's league system.
Eldense have had a big turnaround this summer in terms of players, with their standout arrival proving to be midfielder Victor Camarasa, who has previously played for Cardiff City and Crystal Palace on loan.
Sunderland friendly form:
Team News
Eldense should have a number of debutants on show in this match, with Camarasa, Dani Martin, Victor Garcia, Fran Gamez, Simo Bouzaidi and Nacho Quintana all set to be involved.
Florin Andone is likely to lead the line for the Spanish outfit, while there is also expected to be a spot in central midfield for the experienced David Timor.
This will be head coach Ponz's first match in charge in his second spell at the club, so the manager will want to have a good look at his squad over the course of pre-season.
As for Sunderland, Dan Ballard is missing for the next six weeks due to the knee injury that he picked up in the clash with South Shields.
However, a 31-man squad for the pre-season trip to Spain did include Dennis Cirkin, who is working his way back from a serious hamstring injury.
There will again be wholesale changes throughout Sunday's contest, but new signings Browne and Moore are expected to be in the starting XI on Sunday afternoon.
Eldense possible starting lineup:
Martin; V Garcia, Gamez, Pina, A Martinez; Camarasa, Quintana, Timor; Juanto, Andone, Mateu
Sunderland possible starting lineup:
Moore; Hume, O'Nien, Hjelde, Cirkin; Ekwah, Rigg, Browne; Aouchiche, Mayenda, Clarke
We say: Eldense 1-2 Sunderland
Sunderland are further ahead in their preparations and will be the favourites to win on Sunday, but Eldense certainly have the players to hurt the English club. We are expecting a close game in terms of the scoreline, but the Black Cats should be able to navigate their way to a win.