diff --git a/samtools.wdl b/samtools.wdl
index ff2daf0d74058fab973c1b523c6bc1553aa71734..0d43015794579ba27f7ce58d7d3b144ea778f58f 100644
--- a/samtools.wdl
+++ b/samtools.wdl
@@ -36,11 +36,10 @@ task Index {
     }
 
     output {
+        File index = select_first(flatten([[bamIndexPath], glob(sub(basename(bamFile), "\.bam$", "") + "*.bai")]))
         IndexedBamFile outputBam = object {
           file: bamFile,
-          index: if defined(bamIndexPath)
-                              then select_first([bamIndexPath])
-                              else bamFile + ".bai"
+          index: index
         }
     }
 }