diff --git a/src/messages/block.cpp b/src/messages/block.cpp
index 85b280dd1..0046b3221 100644
--- a/src/messages/block.cpp
+++ b/src/messages/block.cpp
@@ -49,16 +49,22 @@ typename block::cptr block::deserialize(uint32_t version,
     header.set_hash(bitcoin_hash(header_size, data.data()));
     auto begin = std::next(data.data(), header_size);
 
+    auto coinbase = true;
     for (const auto& tx: *message->block_ptr->transactions_ptr())
     {
+        // TODO: consider having tx cache serialized sizes.
         const auto true_size = tx->serialized_size(true);
         ////tx->set_witness_hash(bitcoin_hash(true_size, begin));
 
         // If segregated the hashes are distinct, cache both.
         if (tx->is_segregated())
         {
-            const auto end = std::next(begin, tx->serialized_size(false));
-            tx->set_hash(transaction::desegregated_hash({ begin, end }));
+            // Coinbase witness hash is null_hash, do not cache.
+            if (!coinbase)
+            {
+                const auto end = std::next(begin, tx->serialized_size(false));
+                tx->set_hash(transaction::desegregated_hash({ begin, end }));
+            }
         }
         else
         {
@@ -66,6 +72,7 @@ typename block::cptr block::deserialize(uint32_t version,
             tx->set_hash(bitcoin_hash(true_size, begin));
         }
 
+        coinbase = false;
         std::advance(begin, true_size);
     }