diff --git a/lib/manager/bundler/extract.ts b/lib/manager/bundler/extract.ts
index cbbaab43a10f10e6255d30d0e7e30c3fe93aba4c..f4c7e9a3a1bf189bb47785f737c417dd0c4329bc 100644
--- a/lib/manager/bundler/extract.ts
+++ b/lib/manager/bundler/extract.ts
@@ -109,7 +109,7 @@ export async function extractPackageFile(
           sourceLine = lines[lineNumber];
           // istanbul ignore if
           if (!sourceLine) {
-            logger.error({ content, filename }, 'Undefined sourceLine');
+            logger.error({ content, fileName }, 'Undefined sourceLine');
             sourceLine = 'end';
           }
           if (sourceLine !== 'end') {