diff --git a/lib/manager/gomod/update.js b/lib/manager/gomod/update.js
index 2c5fae4c95b8f89c1aaf08204fa17f464d4ea626..02b24388c2fa61a848470d42282595ca952e7ad5 100644
--- a/lib/manager/gomod/update.js
+++ b/lib/manager/gomod/update.js
@@ -5,8 +5,9 @@ module.exports = {
 };
 
 function updateDependency(currentFileContent, upgrade) {
+  const { depName } = upgrade;
   try {
-    const depNameNoVersion = upgrade.depName
+    const depNameNoVersion = depName
       .split('/')
       .slice(0, 3)
       .join('/');
@@ -17,6 +18,10 @@ function updateDependency(currentFileContent, upgrade) {
       !lineToChange.includes(depNameNoVersion) &&
       !lineToChange.includes('rethinkdb/rethinkdb-go.v5')
     ) {
+      logger.debug(
+        { lineToChange, depName },
+        "go.mod current line doesn't contain dependency"
+      );
       return null;
     }
     let requireLine;
@@ -45,8 +50,8 @@ function updateDependency(currentFileContent, upgrade) {
       newLine = lineToChange.replace(requireLine, `$1$2${upgrade.newValue}`);
     }
     if (upgrade.updateType === 'major') {
-      if (upgrade.depName.startsWith('gopkg.in/')) {
-        const oldV = upgrade.depName.split('.').pop();
+      if (depName.startsWith('gopkg.in/')) {
+        const oldV = depName.split('.').pop();
         newLine = newLine.replace(`.${oldV}`, `.v${upgrade.newMajor}`);
         // Package renames - I couldn't think of a better place to do this
         newLine = newLine.replace(