diff --git a/src/elo.rs b/src/elo.rs
index a17350e..354e95f 100644
--- a/src/elo.rs
+++ b/src/elo.rs
@@ -105,7 +105,6 @@ impl std::fmt::Display for PlayerArena {
 
 impl PlayerArena {
     pub fn new(players: Vec<(String, Box<dyn Fn(Piece) -> Box<dyn Agent>>)>) -> Self {
-        let len = players.len();
         Self {
             players: players
                 .into_iter()
@@ -117,13 +116,16 @@ impl PlayerArena {
 
     fn play(&mut self, pairs: &[(usize, usize)]) {
         pairs
-            .iter()
+            .into_iter()
             .map(|&(i, j)| {
                 (
                     (i, j),
                     Self::create_agents(&self.players[i].1, &self.players[j].1),
                 )
             })
+            .collect::<Vec<_>>()
+            // .into_iter()
+            .into_par_iter()
             .map(|((i, j), (p1, p2))| (i, j, Self::play_two_inner(p1, p2)))
             .collect::<Vec<_>>()
             .into_iter()
@@ -156,18 +158,6 @@ impl PlayerArena {
         self.players[player2].2 = np2;
     }
 
-    fn play_two(&mut self, player1: usize, player2: usize) {
-        println!(
-            "{} vs {}...",
-            self.players[player1].0, self.players[player2].0
-        );
-
-        let (p1, p2) = Self::create_agents(&self.players[player1].1, &self.players[player2].1);
-
-        let outcome = Self::play_two_inner(p1, p2);
-        self.process_outcome(player1, player2, &outcome);
-    }
-
     fn create_agents(
         player_1_fn: &Box<dyn Fn(Piece) -> Box<dyn Agent>>,
         player_2_fn: &Box<dyn Fn(Piece) -> Box<dyn Agent>>,