Haaland's accomplishment marks the first time a player has scored five or more goals in an FA Cup match for a top-flight club since George Best in 1970, with Kevin de Bruyne assisting in the first four goals.
Virgil van Dijk, Cody Gakpo, Luis Diaz, and Harvey Elliott's goals further solidified Liverpool's lead at the top of the table, extending their advantage to four points over second-place Manchester City
Sean Longstaff provided Newcastle with the lead twice in the first half, but Luton responded on both occasions, first with Gabriel Osho and later with Ross Barkley.