diff --git a/src/preserves.nim b/src/preserves.nim
index 6dd0ccd..2ced976 100644
--- a/src/preserves.nim
+++ b/src/preserves.nim
@@ -882,12 +882,13 @@ proc fromPreserve*[T, E](v: var T; pr: Preserve[E]): bool =
         var i: int
         for name, field in fieldPairs(v):
           when v.dot(name).hasCustomPragma(preservesTupleTail):
-            setLen(v.dot(name), pr.len - i)
-            var j: int
-            while result and i < pr.len:
-              result = result and fieldFromPreserve(name, v.dot(name)[j], pr.sequence[i])
-              inc i
-              inc j
+            if pr.len >= i:
+              setLen(v.dot(name), pr.len - i)
+              var j: int
+              while result and i < pr.len:
+                result = result and fieldFromPreserve(name, v.dot(name)[j], pr.sequence[i])
+                inc i
+                inc j
           else:
             if result and i < pr.len:
               result = result and fieldFromPreserve(name, field, pr.sequence[i])