diff --git a/lib/jekyll/converters/markdown.rb b/lib/jekyll/converters/markdown.rb
index 67f7a06baa0..3c6ba5399da 100644
--- a/lib/jekyll/converters/markdown.rb
+++ b/lib/jekyll/converters/markdown.rb
@@ -15,7 +15,7 @@ def setup
 
             @renderer ||= Class.new(Redcarpet::Render::HTML) do
               def block_code(code, lang)
-                lang ||= 'text'
+                lang = lang && lang.split.first || "text"
                 output = add_code_tags(
                   Pygments.highlight(code, :lexer => lang, :options => { :encoding => 'utf-8' }),
                   lang