All Blacks backrower Keiran Read will miss the Crusaders' Super rugby semifinal against the Chiefs on Saturday because of a cracked rib.

Read was hurt during the Crusaders' match against the Chiefs in the second-to-last round of the regular season.

An initial scan showed no sign of a fracture but subsequent tests revealed the injury which forced Read to miss last weekend's playoffs match against the Bulls.

Read says he hopes to recover to be available if the Crusaders make the final.

In his absence, All Blacks captain Richie McCaw will remain at No. 8.