diff -r 0031683bfa76 -r 852682c2003f rust/hedgewars-server/src/core/server.rs
--- a/rust/hedgewars-server/src/core/server.rs	Sat Apr 11 23:20:09 2020 +0300
+++ b/rust/hedgewars-server/src/core/server.rs	Sun Apr 12 00:02:11 2020 +0300
@@ -989,12 +989,15 @@
         if client_left {
             client.set_is_in_game(false);
 
-            let team_names: Vec<_> = room
-                .client_teams(client.id)
-                .map(|t| t.name.clone())
-                .collect();
+            if let Some(ref mut info) = room.game_info {
+                let team_names: Vec<_> = info
+                    .client_teams(client.id)
+                    .map(|t| t.name.clone())
+                    .collect();
 
-            if let Some(ref mut info) = room.game_info {
+                info.left_teams.extend(team_names.iter().cloned());
+                info.ingame_teams_count -= team_names.len() as u8;
+
                 for team_name in &team_names {
                     let remove_msg =
                         utils::to_engine_msg(std::iter::once(b'F').chain(team_name.bytes()));
@@ -1008,7 +1011,7 @@
                 }
                 Some(team_names)
             } else {
-                unreachable!();
+                None
             }
         } else {
             None
@@ -1125,6 +1128,7 @@
 
         if !team_names.is_empty() {
             info.left_teams.retain(|name| !team_names.contains(&name));
+            info.ingame_teams_count += team_names.len() as u8;
         }
     }
 }