diff --git a/pallets/collator-assignment/src/benchmarking.rs b/pallets/collator-assignment/src/benchmarking.rs
index f2b876c9c..851fbdfd3 100644
--- a/pallets/collator-assignment/src/benchmarking.rs
+++ b/pallets/collator-assignment/src/benchmarking.rs
@@ -85,10 +85,11 @@ mod benchmarks {
         <CollatorContainerChain<T>>::put(&old_assigned);
         // Do not use [0; 32] because that seed will not shuffle the list of collators
         let random_seed = [1; 32];
+        <Randomness<T>>::put(random_seed);
 
         #[block]
         {
-            <Pallet<T>>::initializer_on_new_session(&session_index, random_seed, collators);
+            <Pallet<T>>::initializer_on_new_session(&session_index, collators);
         }
 
         // Assignment changed
diff --git a/pallets/collator-assignment/src/mock.rs b/pallets/collator-assignment/src/mock.rs
index b6c9b721f..db2e8f5bd 100644
--- a/pallets/collator-assignment/src/mock.rs
+++ b/pallets/collator-assignment/src/mock.rs
@@ -14,8 +14,6 @@
 // You should have received a copy of the GNU General Public License
 // along with Tanssi.  If not, see <http://www.gnu.org/licenses/>
 
-use frame_support::traits::Hooks;
-
 use {
     crate::{
         self as pallet_collator_assignment, GetRandomnessForNextBlock,
@@ -23,7 +21,7 @@ use {
     },
     frame_support::{
         parameter_types,
-        traits::{ConstU16, ConstU64},
+        traits::{ConstU16, ConstU64, Hooks},
     },
     frame_system as system,
     parity_scale_codec::{Decode, Encode},