Will Jordan scored a double and Codie Taylor got another as the Crusaders confirmed top spot and a home final.
The Crusaders will host the 2021 Super Rugby Aotaeroa final against the Chiefs after returning to winning ways with a 29-6 victory over the Blues on Sunday in Christchurch.
The 2020 Super Rugby Aotaeroa champions scored four tries to the Blues' none, with two from Will Jordan including a fine solo run to open the scoring in the seventh minute.
Sevu Reece and Codie Taylor also crossed for the Canterbury side who led 12-0 at the interval and never looked back.
Taylor remains the leading try scorer this season, getting his seventh of 2021 on the hour when the Crusaders maul forced their way over following a line-out.
The result also means that the Blues can no longer mathematically make for the top two thus will not feature in the decider despite having a game in hand against the Chiefs in Round 10, having collected no points on Sunday.
The Blues have lost four of their past five matches, fading from contention after a promising 2-0 start.
The Crusaders had gone down 26-25 to the Chiefs in Round Eight, putting at jeopardy their hopes of hosting the Final but Sunday's result ended any doubts.
Scott Robertson's side have been top of the table since Round Two, having started the 2021 season with five straight wins.