diff --git a/app/controllers/concerns/completions_concern.rb b/app/controllers/concerns/completions_concern.rb
new file mode 100644
index 0000000..db8b1e1
--- /dev/null
+++ b/app/controllers/concerns/completions_concern.rb
@@ -0,0 +1,30 @@
+module CompletionsConcern
+  extend ActiveSupport::Concern
+
+  def pad(n)
+    if n > 9
+      return n.to_s
+    end
+    "0" + n.to_s
+  end
+
+  def display_time(seconds)
+    if seconds > 3600
+      hours = seconds / 3600
+      return hours.to_s + ":" + display_time(seconds % 3600)
+    elsif seconds > 60
+      minutes = seconds / 60
+      return pad(minutes) + ":" + display_time(seconds % 60)
+    end
+    pad(seconds)
+  end
+
+  def extend_completions!(completions)
+    current_time_from_start = 0
+    @completions.each do |completion|
+      completion.display_time_from_start = display_time(completion.time_seconds)
+      completion.display_relative_time = display_time(completion.time_seconds - current_time_from_start)
+      current_time_from_start += completion.time_seconds
+    end
+  end
+end
diff --git a/app/controllers/contestants_controller.rb b/app/controllers/contestants_controller.rb
index bed28ec..805b129 100644
--- a/app/controllers/contestants_controller.rb
+++ b/app/controllers/contestants_controller.rb
@@ -1,4 +1,6 @@
 class ContestantsController < ApplicationController
+  include CompletionsConcern
+
   before_action :set_contest
   before_action :set_contestant, only: %i[ destroy edit update]
   before_action :set_completions, only: %i[edit update ]
@@ -57,32 +59,10 @@ class ContestantsController < ApplicationController
     @contestant = Contestant.find(params[:id])
   end
 
-  def pad(n)
-    if n > 9
-      return n.to_s
-    end
-    "0" + n.to_s
-  end
-
-  def display_time(seconds)
-    if seconds > 3600
-      hours = seconds / 3600
-      return hours.to_s + ":" + display_time(seconds % 3600)
-    elsif seconds > 60
-      minutes = seconds / 60
-      return pad(minutes) + ":" + display_time(seconds % 60)
-    end
-    pad(seconds)
-  end
-
   def set_completions
     @completions = @contestant.completions.order(:time_seconds)
-    current_time_from_start = 0
-    @completions.each do |completion|
-      completion.display_time_from_start = display_time(completion.time_seconds)
-      completion.display_relative_time = display_time(completion.time_seconds - current_time_from_start)
-      current_time_from_start += completion.time_seconds
-    end
+    extend_completions!(@completions)
+    @completions
   end
 
   def contestant_params
diff --git a/app/controllers/contests_controller.rb b/app/controllers/contests_controller.rb
index ecca06e..cf473ca 100644
--- a/app/controllers/contests_controller.rb
+++ b/app/controllers/contests_controller.rb
@@ -1,4 +1,6 @@
 class ContestsController < ApplicationController
+  include CompletionsConcern
+
   before_action :set_contest, only: %i[ destroy edit show update ]
   skip_before_action :require_authentication, only: %i[ scoreboard ]
 
@@ -68,6 +70,7 @@ class ContestsController < ApplicationController
     @title = @contest.name
     @contestants = @contest.contestants.order(:name)
     @puzzles = @contest.puzzles.order(:id)
+    extend_completions!(@contest.completions)
     render :scoreboard
   end