diff --git a/store-implementation/proxy-store/src/main/java/uk/gov/gchq/gaffer/proxystore/response/deserialiser/impl/DefaultResponseDeserialiser.java b/store-implementation/proxy-store/src/main/java/uk/gov/gchq/gaffer/proxystore/response/deserialiser/impl/DefaultResponseDeserialiser.java
index 9dffbc03611..8ca170ff264 100644
--- a/store-implementation/proxy-store/src/main/java/uk/gov/gchq/gaffer/proxystore/response/deserialiser/impl/DefaultResponseDeserialiser.java
+++ b/store-implementation/proxy-store/src/main/java/uk/gov/gchq/gaffer/proxystore/response/deserialiser/impl/DefaultResponseDeserialiser.java
@@ -38,7 +38,7 @@ public DefaultResponseDeserialiser(final TypeReference<O> typeReference) {
     @Override
     public O deserialise(final String jsonString) throws SerialisationException {
         // Special handling for String values returned while using the ProxyStore
-        if (typeReference.getType().equals(Object.class) && !jsonString.matches("^(-?\\d*\\.?\\d*|false|true|null|\\[.*\\]|\\{.*\\})$")) {
+        if (typeReference.getType().equals(Object.class) && !jsonString.matches("^(-?\\d*\\.?\\d*|false|true|null|\\[.*\\]|\\.*\\})$")) {
             // The input is likely a plain java.lang.String object, so return as-is
             return (O) jsonString;
         } else {