Update: 1:00PM Skipper Kieran Read will again be on the sidelines when the Crusaders take on Super Rugby leaders the Sharks in Christchurch as he continues his recovery from concussion.
The All Blacks No.8 has missed the Crusaders' last two matches, including last weekend's 57-29 win over the Reds, after his second head knock in a month forced him off the field against the Chiefs in mid-April.
Coach Todd Blackadder says Read was ruled out of contention early in the week after still showing minor signs of concussion.
"Given that it's been a short week for us to prepare anyway due to a late flight back from Brisbane, we decided the sensible thing to do was to make the call early that he wouldn't be available," he said.
"He hasn't been able to fully participate in contact training for a little while so we're better off giving him more space and time to get back to 100 per cent."
Blackadder has made three changes to his starting 15 for the match on Saturday night, including bringing in Tom Taylor at fullback and resting Israel Dagg.
"Leaving Izzy out of the mix this week is purely preventative," he said.
"We've been really happy with the way he's been playing, but there are some early signs of wear and tear and we just want to make sure that we manage that so he can continue to play at his best."
At lock, Dominic Bird comes in for Luke Romano, who is out with a broken ankle.
Blackadder has again rotated his halfbacks, with Willi Heinz starting and Andy Ellis on the bench.
The Crusaders have won their past five matches, and seven of their last eight, to climb to fourth on the table, while the Sharks are coming off a 16-9 defeat to the Brumbies in Canberra.
Crusaders: Tom Taylor, Johnny McNicholl, Rey Lee-Lo, Ryan Crotty (capt), Nemani Nadolo, Colin Slade, Willie Heinz, Luke Whitelock, Richie McCaw, Jordan Taufua, Sam Whitelock, Dominic Bird, Owen Franks, Corey Flynn, Wyatt Crockett. Reserves: Ben Funnell, Tim Perry, Nepo Laulala, Jimmy Tupou, George Whitelock, Andy Ellis, Tyler Bleyendaal, Nafi Tuitavake.