Albion take on the Mariners in the first ever FA Cup quarter final to be played in Brighton.
Robert Sanchez returns in goal and Deniz Undav gets another chance up front.
Roberto De Zerbi has fielded a strong side, including Pascal Gross, Solly March, Alexis Mac Allister, Kaoru Mitoma, Evan Ferguson and Moises Caiceo.
Grimsby fans are out in force, with more than 4,000 of them in attendance.