diff --git a/lib/winston/create-logger.js b/lib/winston/create-logger.js
index e868aeaad..e390dd7c1 100644
--- a/lib/winston/create-logger.js
+++ b/lib/winston/create-logger.js
@@ -76,9 +76,10 @@ module.exports = function (opts = {}) {
       if (args.length === 1) {
         const [msg] = args;
         const info = msg && msg.message && msg || { message: msg };
-        info.level = info[LEVEL] = level;
-        self._addDefaultMeta(info);
-        self.write(info);
+        const cloneInfo = Object.assign(Object.create(info), info)
+        cloneInfo.level = cloneInfo[LEVEL] = level;
+        self._addDefaultMeta(cloneInfo);
+        self.write(cloneInfo);
         return (this || logger);
       }
 
diff --git a/test/unit/winston/logger.test.js b/test/unit/winston/logger.test.js
index 83504f594..d59c9dad4 100755
--- a/test/unit/winston/logger.test.js
+++ b/test/unit/winston/logger.test.js
@@ -701,7 +701,6 @@ describe('Logger Instance', function () {
 
         const logger = helpers.createLogger(function (info) {
           assume(info).instanceOf(Error);
-          assume(info).equals(err);
           done();
         });
 
@@ -772,7 +771,6 @@ describe('Logger Instance', function () {
         const err = new Error('test');
         const logger = helpers.createLogger(function (info) {
           assume(info).instanceOf(Error);
-          assume(info).equals(err);
           done();
         });
 
@@ -959,7 +957,6 @@ describe('Logger Instance', function () {
         const err = new Error('test');
         const logger = helpers.createLogger(function (info) {
           assume(info).instanceOf(Error);
-          assume(info).equals(err);
           done();
         });