diff --git a/crates/bin/prove_block/src/lib.rs b/crates/bin/prove_block/src/lib.rs
index f0bd0f0b..f179fbbc 100644
--- a/crates/bin/prove_block/src/lib.rs
+++ b/crates/bin/prove_block/src/lib.rs
@@ -309,8 +309,15 @@ pub async fn prove_block(
     let updated_root = block_hash_storage_proof.class_commitment.unwrap_or(Felt::ZERO);
     let previous_root = previous_block_hash_storage_proof.class_commitment.unwrap_or(Felt::ZERO);
 
-    let previous_contract_trie_root = previous_block_hash_storage_proof.contract_proof[0].hash::<PedersenHash>();
-    let current_contract_trie_root = block_hash_storage_proof.contract_proof[0].hash::<PedersenHash>();
+    // On devnet and until block 10, the storage_root_idx might be None and that means that contract_proof is empty
+    let previous_contract_trie_root = match previous_block_hash_storage_proof.contract_proof.first() {
+        Some(proof) => proof.hash::<PedersenHash>(),
+        None => Felt252::ZERO,
+    };
+    let current_contract_trie_root = match block_hash_storage_proof.contract_proof.first() {
+        Some(proof) => proof.hash::<PedersenHash>(),
+        None => Felt252::ZERO,
+    };
 
     let previous_contract_proofs: Vec<_> =
         previous_storage_proofs.values().map(|proof| proof.contract_proof.clone()).collect();
diff --git a/crates/bin/prove_block/src/reexecute.rs b/crates/bin/prove_block/src/reexecute.rs
index ba33e3ce..15c49195 100644
--- a/crates/bin/prove_block/src/reexecute.rs
+++ b/crates/bin/prove_block/src/reexecute.rs
@@ -10,7 +10,7 @@ use blockifier::transaction::objects::TransactionExecutionInfo;
 use blockifier::transaction::transaction_execution::Transaction;
 use blockifier::transaction::transactions::ExecutableTransaction;
 use cairo_vm::Felt252;
-use rpc_client::pathfinder::proofs::{PathfinderProof, TrieNode};
+use rpc_client::pathfinder::proofs::{ContractData, PathfinderProof, TrieNode};
 use rpc_client::RpcClient;
 use starknet::core::types::{BlockId, StarknetError};
 use starknet::providers::{Provider as _, ProviderError};
@@ -163,8 +163,11 @@ pub(crate) fn format_commitment_facts<H: HashFunctionType>(
 impl PerContractStorage for ProverPerContractStorage {
     async fn compute_commitment(&mut self) -> Result<CommitmentInfo, CommitmentInfoError> {
         // TODO: error code
-        let contract_data =
-            self.storage_proof.contract_data.as_ref().expect("storage proof should have a contract_data field");
+        let contract_data = match self.storage_proof.contract_data.as_ref() {
+            None => &ContractData::default(),
+            Some(data) => data,
+        };
+
         let updated_root = contract_data.root;
 
         let commitment_facts = format_commitment_facts::<PedersenHash>(&contract_data.storage_proofs);
diff --git a/crates/rpc-client/src/pathfinder/proofs.rs b/crates/rpc-client/src/pathfinder/proofs.rs
index 500156f1..f0315a40 100644
--- a/crates/rpc-client/src/pathfinder/proofs.rs
+++ b/crates/rpc-client/src/pathfinder/proofs.rs
@@ -38,7 +38,7 @@ impl TrieNode {
     }
 }
 
-#[derive(Debug, Clone, Deserialize)]
+#[derive(Debug, Clone, Deserialize, Default)]
 pub struct ContractData {
     /// Root of the Contract state tree
     pub root: Felt,
@@ -75,7 +75,7 @@ impl ContractData {
 
 #[derive(Debug, Clone, Deserialize)]
 pub struct PathfinderProof {
-    pub state_commitment: Felt,
+    pub state_commitment: Option<Felt>,
     pub class_commitment: Option<Felt>,
     pub contract_proof: Vec<TrieNode>,
     pub contract_data: Option<ContractData>,