diff --git a/pkg/kv/kvclient/kvcoord/txn_interceptor_committer.go b/pkg/kv/kvclient/kvcoord/txn_interceptor_committer.go
index a408f2438a4c..572217d6b4b7 100644
--- a/pkg/kv/kvclient/kvcoord/txn_interceptor_committer.go
+++ b/pkg/kv/kvclient/kvcoord/txn_interceptor_committer.go
@@ -452,7 +452,7 @@ func (tc *txnCommitter) retryTxnCommitAfterFailedParallelCommit(
 		et := baSuffix.Requests[0].GetEndTxn().ShallowCopy().(*kvpb.EndTxnRequest)
 		et.LockSpans, _ = mergeIntoSpans(et.LockSpans, et.InFlightWrites)
 		et.InFlightWrites = nil
-		baSuffix.Requests[0].Value.(*kvpb.RequestUnion_EndTxn).EndTxn = et
+		baSuffix.Requests[0].MustSetInner(et)
 	}
 	brSuffix, pErr := tc.wrapped.SendLocked(ctx, baSuffix)
 	if pErr != nil {
diff --git a/pkg/kv/kvclient/kvcoord/txn_interceptor_span_refresher.go b/pkg/kv/kvclient/kvcoord/txn_interceptor_span_refresher.go
index 64e19117c1b3..59b4443a52ac 100644
--- a/pkg/kv/kvclient/kvcoord/txn_interceptor_span_refresher.go
+++ b/pkg/kv/kvclient/kvcoord/txn_interceptor_span_refresher.go
@@ -408,7 +408,7 @@ func (sr *txnSpanRefresher) splitEndTxnAndRetrySend(
 		et = et.ShallowCopy().(*kvpb.EndTxnRequest)
 		et.LockSpans, _ = mergeIntoSpans(et.LockSpans, et.InFlightWrites)
 		et.InFlightWrites = nil
-		baSuffix.Requests[0].Value.(*kvpb.RequestUnion_EndTxn).EndTxn = et
+		baSuffix.Requests[0].MustSetInner(et)
 	}
 	brSuffix, pErr := sr.SendLocked(ctx, baSuffix)
 	if pErr != nil {