diff --git a/lib/gfa/graph.rb b/lib/gfa/graph.rb
index 993a8ce..cf6a002 100644
--- a/lib/gfa/graph.rb
+++ b/lib/gfa/graph.rb
@@ -120,7 +120,7 @@ def linking_records(segments, degree: 1)
       raise "Unrecognised class: #{segments.class}"
     end
 
-    edge_matrix # Just to trigger matrix calculation
+    edge_matrix unless degree == 0 # Just to trigger matrix calculation
     degree.times do |round|
       $stderr.puts "- Expansion round #{round + 1}"
       self.class.advance_bar(segments.size)
diff --git a/lib/gfa/version.rb b/lib/gfa/version.rb
index e6cf0c4..bc874e0 100644
--- a/lib/gfa/version.rb
+++ b/lib/gfa/version.rb
@@ -1,5 +1,5 @@
 class GFA
-  VERSION       = '0.9.0'
+  VERSION       = '0.9.1'
   VERSION_ARRAY = VERSION.split(/\./).map { |x| x.to_i } # :nodoc:
   VERSION_MAJOR = VERSION_ARRAY[0] # :nodoc:
   VERSION_MINOR = VERSION_ARRAY[1] # :nodoc: