diff --git a/zebra-network/src/protocol/external/codec.rs b/zebra-network/src/protocol/external/codec.rs
index 9006701b7..e18417c3d 100644
--- a/zebra-network/src/protocol/external/codec.rs
+++ b/zebra-network/src/protocol/external/codec.rs
@@ -203,13 +203,7 @@ impl Codec {
             }
             Addr(ref addrs) => addrs.zcash_serialize(&mut writer)?,
             GetAddr => { /* Empty payload -- no-op */ }
-            Block {
-                ref version,
-                ref block,
-            } => {
-                writer.write_u32::<LittleEndian>(version.0)?;
-                block.zcash_serialize(&mut writer)?
-            }
+            Block(ref block) => block.zcash_serialize(&mut writer)?,
             GetBlocks {
                 ref version,
                 ref block_locator_hashes,
@@ -232,13 +226,7 @@ impl Codec {
             Inv(ref hashes) => hashes.zcash_serialize(&mut writer)?,
             GetData(ref hashes) => hashes.zcash_serialize(&mut writer)?,
             NotFound(ref hashes) => hashes.zcash_serialize(&mut writer)?,
-            Tx {
-                ref version,
-                ref transaction,
-            } => {
-                writer.write_u32::<LittleEndian>(version.0)?;
-                transaction.zcash_serialize(&mut writer)?
-            }
+            Tx(ref transaction) => transaction.zcash_serialize(&mut writer)?,
             Mempool => { /* Empty payload -- no-op */ }
             FilterLoad {
                 ref filter,
@@ -465,10 +453,7 @@ impl Codec {
     }
 
     fn read_block<R: Read>(&self, mut reader: R) -> Result<Message, Error> {
-        Ok(Message::Block {
-            version: Version(reader.read_u32::<LittleEndian>()?),
-            block: Box::new(Block::zcash_deserialize(&mut reader)?),
-        })
+        Ok(Message::Block(Box::new(Block::zcash_deserialize(reader)?)))
     }
 
     fn read_getblocks<R: Read>(&self, mut reader: R) -> Result<Message, Error> {
@@ -508,11 +493,8 @@ impl Codec {
         Ok(Message::NotFound(Vec::zcash_deserialize(reader)?))
     }
 
-    fn read_tx<R: Read>(&self, mut reader: R) -> Result<Message, Error> {
-        Ok(Message::Tx {
-            version: Version(reader.read_u32::<LittleEndian>()?),
-            transaction: Box::new(Transaction::zcash_deserialize(&mut reader)?),
-        })
+    fn read_tx<R: Read>(&self, mut rdr: R) -> Result<Message, Error> {
+        Ok(Message::Tx(Box::new(Transaction::zcash_deserialize(rdr)?)))
     }
 
     fn read_mempool<R: Read>(&self, mut _reader: R) -> Result<Message, Error> {
diff --git a/zebra-network/src/protocol/external/message.rs b/zebra-network/src/protocol/external/message.rs
index 12b72be1a..29809aec4 100644
--- a/zebra-network/src/protocol/external/message.rs
+++ b/zebra-network/src/protocol/external/message.rs
@@ -132,14 +132,7 @@ pub enum Message {
     /// A `block` message.
     ///
     /// [Bitcoin reference](https://en.bitcoin.it/wiki/Protocol_documentation#block)
-    Block {
-        /// Transaction data format version (note, this is signed).
-        // XXX does this get folded into the Block struct?
-        version: Version,
-
-        /// The block itself.
-        block: Box<Block>,
-    },
+    Block(Box<Block>),
 
     /// A `getblocks` message.
     ///
@@ -252,16 +245,7 @@ pub enum Message {
     /// A `tx` message.
     ///
     /// [Bitcoin reference](https://en.bitcoin.it/wiki/Protocol_documentation#tx)
-    // `flag` is not included (it's optional), and therefore
-    // `tx_witnesses` aren't either, as they go if `flag` goes.
-    Tx {
-        /// Transaction data format version (note, this is signed).
-        // XXX do we still need this with the transaction data handling?
-        version: Version,
-
-        /// The `Transaction` type itself.
-        transaction: Box<Transaction>,
-    },
+    Tx(Box<Transaction>),
 
     /// A `mempool` message.
     ///