diff --git a/Library/Homebrew/download_queue.rb b/Library/Homebrew/download_queue.rb
index 5787596354..6722f24da6 100644
--- a/Library/Homebrew/download_queue.rb
+++ b/Library/Homebrew/download_queue.rb
@@ -36,7 +36,9 @@ module Homebrew
 
     sig { void }
     def fetch
-      if concurrency == 1
+      return if downloads.empty?
+
+      if concurrency == 1 || downloads.one?
         downloads.each do |downloadable, promise|
           promise.wait!
         rescue ChecksumMismatchError => e