The veteran hooker was the major casualty of the Warriors' awful defeat in Newcastle last Saturday, losing his place in the starting lineup to Nathaniel Roache for the home match against the Raiders on Sunday.
Coach Stephen Kearney said it wasn't a difficult decision, and Luke was well below par as the Auckland club fell to their fifth consecutive loss.
But many others are lucky to keep their spots, with only four or five players emerging with any credit from Saturday's match.
Kearney doesn't have too many choices - due to the number of injuries - but must have been tempted to consider more changes after the abject display.
Luke has had a mixed season. In some games his running game has been prominent, and Luke has been generally reliable and diligent on defence. But his distribution has varied in quality and mistakes at crucial moments have blunted his impact. He gave up a cheap error on Saturday, sent an early kickoff out on the full and didn't really test the defence from dummy half.
"It's purely form," Kearney told Radio Sport. "As I have always said if there is an option to come in and do a better job then I will be exercising that option. Issac would be very disappointed with his performance, and wants the opportunity to make up for it and I am sure he will do over time. It's based on what I thought was best for the team."
Roache is set to start for just the third time in what will be his 20th NRL match.
In his first game back from a hamstring injury, the 21-year-old Roache made an instant impact after coming on at halftime. His sharp runs added some momentum to the Warriors attack, before he switched to the right wing to replace the injured David Fusitu'a.
Roache made 120m from 10 carries (including four from dummy half), 13 tackles without a miss, two line breaks, a line break assist, four tackle breaks, two off loads and two kicks as well as his first NRL try.
In a boost for the Warriors, second rower Ryan Hoffman returns from six weeks on the sideline, after last appearing in the 21-14 home win over Canterbury -Bankstown in late June. Hoffman's return means Bunty Afoa is set to start on the right edge with Isaiah Papali'i - originally named to start last week - on the bench.
Others on the extended bench are Sam Lisone, James Bell, Chris Satae, Charnze Nicoll-Klokstad, Jazz Tevaga and Ata Hingano.
Ominously, the Raiders have found form over the last month. After a run of defeats, they've won three of their last four matches to sit four points outside the top eight.
Warriors v Canberra Raiders
Mount Smart Stadium, Auckland
4.00pm, Sunday, August 13
Warriors
1 Roger Tuivasa-Sheck (c)
2 David Fusitu'a
3 Blake Ayshford
4 Solomone Kata
5 Ken Maumalo
6 Kieran Foran
7 Mason Lino
8 Jacob Lillyman
9 Nathaniel Roache
10 Ben Matulino
11 Bunty Afoa
12 Ryan Hoffman
13 Simon Mannering
Interchange:
14 Issac Luke
15 Sam Lisone
16 Isaiah Papali'i
17 James Bell
18 Jazz Tevaga
20 Chris Satae
21 Mafoa'aeata Hingano
22 Charnze Nicoll-Klokstad
