Whitelock had some concussion symptoms after training yesterday and withdrew from the side today.
He left the field early last week against the Hurricanes after failing a head injury assessment test, and despite initially recovering well, he now cannot complete the Post-Concussion Return to Play process.
The Canterbury side have a handy replacement to call upon, with Luke Romano now starting alongside Scott Barrett, and Quinten Strange being brought on to the bench. Matt Todd will now captain the side.
The Crusaders were already without Ryan Crotty, who was also ruled out due to a concussion sustained against the Hurricanes.
There is also a change on the bench, with first-five Mike Delany ruled out after jarring his knee at training, with Brett Cameron coming onto the bench as his replacement.
The game at Forsyth Barr Stadium kicks off at 7.35pm.
Crusaders: David Havili, Seta Tamanivalu, Jack Goodhue, Tim Bateman, George Bridge, Mitchell Hunt, Mitchell Drummond, Jordan Taufua, Matt Todd, Heiden Bedwell-Curtis, Luke Romano, Scott Barrett, Michael Alaalatoa, Codie Taylor, Wyatt Crockett.
Reserves: Manasa Mataele, Brett Cameron, Bryn Hall, Billy Harmon, Quinten Strange, Oliver Jager, Chris King, Ben Funnell.
Highlanders: Ben Smith (captain), Waisake Naholo, Rob Thompson, Tei Walden, Tevita Li, Lima Sopoaga, Aaron Smith, Luke Whitelock, Dillon Hunt, Liam Squire, Tom Franklin, Jackson Hemopo, Siate Tokolahi, Liam Coltman, Aki Seiuli.
Reserves: Ash Dixon (co-captain), Daniel Lienert-Brown, Kalolo Tuiloma, Shannon Frizell, Elliot Dixon, Kayne Hammington, Fletcher Smith, Matt Faddes.