Albion's new head coach Fabian Hurzeler has some key decisions to make ahead of his first match in charge at the Amex Stadium.
Villareal, who finished eighth in La Liga last term, will offer a stern test ahead of their Premier League opener at Everton next Saturday on August 17.
Hurzeler has a number of players who have yet to feature in pre-season, including skipper Lewis Dunk and Scotland international midfielder Billy Gilmour.
Dunk and Gilmour were given extended leave following Euro 2024 but both should feature against the Spaniards, despite the uncertainty around Gilmour's future. The 23-year-old is wanted by Napoli and Serie A club are expected to return with increased bids between now and the end of the transfer window.
Here's how Albion could line-up for their final pre-season friendly against Villarreal.
5. Jan Paul van Hecke - CB
Has been excellent in pre-season and could emerge as one of the top defenders in the PL this term. Photo: Masashi Hara
6. Valentin Barco - LB
Missed the QPR friendly with a slight knock but should return at left back for this one Photo: Masashi Hara
7. Carlos Baleba - CM
Played at left back against QOPR but may resume his more familiar role in midfield as Barco returns Photo: Masashi Hara
8. Billy Gilmour - CM
A big call here to see if Gilmour plays or not. Remains on Napoli's wanted list and rumours are Gilmour is open to a move but Brighton are reluctant to sell Photo: Charlie Crowhurst