diff --git a/src/Lean/Message.lean b/src/Lean/Message.lean
index 485b9dce1f..269ceb63de 100644
--- a/src/Lean/Message.lean
+++ b/src/Lean/Message.lean
@@ -287,7 +287,7 @@ instance : ToMessageData Format        := ⟨MessageData.ofFormat⟩
 instance : ToMessageData MessageData   := ⟨id⟩
 instance {α} [ToMessageData α] : ToMessageData (List α)  := ⟨fun as => MessageData.ofList $ as.map toMessageData⟩
 instance {α} [ToMessageData α] : ToMessageData (Array α) := ⟨fun as => toMessageData as.toList⟩
-instance {α} [ToMessageData α] : ToMessageData (Option α) := ⟨fun | none => "none" | some e => "some ({toMessageData e})"⟩
+instance {α} [ToMessageData α] : ToMessageData (Option α) := ⟨fun | none => "none" | some e => "some (" ++ toMessageData e ++ ")"⟩
 instance : ToMessageData (Option Expr) := ⟨fun | none => "<not-available>" | some e => toMessageData e⟩
 
 syntax:max "msg!" (interpolatedStr term) : term