diff --git a/lib/logger.js b/lib/logger.js
index f52da4bd..c899dd33 100644
--- a/lib/logger.js
+++ b/lib/logger.js
@@ -80,19 +80,17 @@ class Logger {
   }
 
   log(level, ...args) {
-    let logLevel = levels.getLevel(level);
+    const logLevel = levels.getLevel(level);
     if (!logLevel) {
-      // allow LOG to be synonym of INFO
-      if ((level && level.trim().indexOf(" ") !== -1) || args.length === 0) {
-        args = [level, ...args];
+      if (configuration.validIdentifier(level) && args.length > 0) {
+        // logLevel not found but of valid signature, WARN before fallback to INFO
+        this.log(levels.WARN, 'log4js:logger.log: valid log-level not found as first parameter given:', level);
+        this.log(levels.INFO, `[${level}]`, ...args);
       } else {
-        this._log(levels.WARN, ['log4js:logger.log: invalid value for log-level as first parameter given:', level]);
-        args = [`[${level}]`, ...args];
+        // apart from fallback, allow .log(...args) to be synonym with .log("INFO", ...args)
+        this.log(levels.INFO, level, ...args);
       }
-      // fallback to INFO
-      logLevel = levels.INFO;
-    }
-    if (this.isLevelEnabled(logLevel)) {
+    } else if (this.isLevelEnabled(logLevel)) {
       this._log(logLevel, args);
     }
   }
diff --git a/test/tap/newLevel-test.js b/test/tap/newLevel-test.js
index d89f1066..ffae2bc0 100644
--- a/test/tap/newLevel-test.js
+++ b/test/tap/newLevel-test.js
@@ -243,14 +243,14 @@ test("../../lib/logger", batch => {
     const events = recording.replay();
 
     t.equal(events[0].level.toString(), "WARN", "should log warning");
-    t.equal(events[0].data[0], "log4js:logger.log: invalid value for log-level as first parameter given:");
+    t.equal(events[0].data[0], "log4js:logger.log: valid log-level not found as first parameter given:");
     t.equal(events[0].data[1], "LEVEL_DOES_NOT_EXIST");
     t.equal(events[1].level.toString(), "INFO", "should fall back to INFO");
     t.equal(events[1].data[0], "[LEVEL_DOES_NOT_EXIST]");
     t.equal(events[1].data[1], "Event 1");
 
     t.equal(events[2].level.toString(), "WARN", "should log warning");
-    t.equal(events[2].data[0], "log4js:logger.log: invalid value for log-level as first parameter given:");
+    t.equal(events[2].data[0], "log4js:logger.log: valid log-level not found as first parameter given:");
     t.equal(events[2].data[1], undefined);
     t.equal(events[3].level.toString(), "INFO", "should fall back to INFO");
     t.equal(events[3].data[0], "[undefined]");