diff --git a/beacon_chain/spec/beaconstate.nim b/beacon_chain/spec/beaconstate.nim
index 984b18c73..445340acd 100644
--- a/beacon_chain/spec/beaconstate.nim
+++ b/beacon_chain/spec/beaconstate.nim
@@ -22,16 +22,26 @@ from ./datatypes/capella import BeaconState, ExecutionPayloadHeader, Withdrawal
 
 export extras, forks, validator, chronicles
 
+var debugTrackedValidator* = ValidatorIndex.high
+
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#increase_balance
 func increase_balance*(balance: var Gwei, delta: Gwei) =
   balance += delta
 
-func increase_balance*(
-    state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei) =
+func increase_balance(
+    state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei,
+    info: typeof(instantiationInfo())) =
   ## Increase the validator balance at index ``index`` by ``delta``.
   if delta != 0: # avoid dirtying the balance cache if not needed
+    {.noSideEffect.}:
+      if index == debugTrackedValidator:
+        debugEcho "+", $delta, " ", $info
     increase_balance(state.balances.mitem(index), delta)
 
+template increase_balance*(
+    state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei) =
+  increase_balance(state, index, delta, instantiationInfo())
+
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#decrease_balance
 func decrease_balance*(balance: var Gwei, delta: Gwei) =
   balance =
@@ -40,13 +50,21 @@ func decrease_balance*(balance: var Gwei, delta: Gwei) =
     else:
       balance - delta
 
-func decrease_balance*(
-    state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei) =
+func decrease_balance(
+    state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei,
+    info: typeof(instantiationInfo())) =
   ## Decrease the validator balance at index ``index`` by ``delta``, with
   ## underflow protection.
   if delta != 0: # avoid dirtying the balance cache if not needed
+    {.noSideEffect.}:
+      if index == debugTrackedValidator:
+        debugEcho "-", $delta, " ", $info
     decrease_balance(state.balances.mitem(index), delta)
 
+template decrease_balance*(
+    state: var ForkyBeaconState, index: ValidatorIndex, delta: Gwei) =
+  decrease_balance(state, index, delta, instantiationInfo())
+
 # https://github.com/ethereum/consensus-specs/blob/v1.4.0-alpha.3/specs/phase0/beacon-chain.md#deposits
 # https://github.com/ethereum/consensus-specs/blob/v1.3.0/specs/altair/beacon-chain.md#modified-apply_deposit
 func get_validator_from_deposit*(deposit: DepositData):
diff --git a/tests/test_block_rewards.nim b/tests/test_block_rewards.nim
index 0810e821a..ad781bda4 100644
--- a/tests/test_block_rewards.nim
+++ b/tests/test_block_rewards.nim
@@ -9,6 +9,7 @@
 
 import
   chronicles,
+  ../../beacon_chain/spec/beaconstate,
   ../../beacon_chain/spec/forks,
   ../../beacon_chain/spec/state_transition,
   ../../beacon_chain/validators/rewards,
@@ -68,6 +69,8 @@ proc runTest(consensusFork: static ConsensusFork,
              state_slot = stateSlot,
              expected_balance = preStateBalance + blockValue
 
+        debugTrackedValidator = ValidatorIndex.high
+
         block:
           let res =
             process_slots(defaultRuntimeConfig, fhPreState[],
@@ -80,6 +83,7 @@ proc runTest(consensusFork: static ConsensusFork,
         let advanceBalance =
           withState(fhPreState[]):
             forkyState.data.balances.item(proposerIndex)
+        debugTrackedValidator = ValidatorIndex(proposerIndex)
 
         block:
           let res =