diff --git a/docs/requirements.md b/docs/requirements.md
index a89e3a8..a8e6922 100644
--- a/docs/requirements.md
+++ b/docs/requirements.md
@@ -285,5 +285,5 @@ A separate executable target (`balancing`) that links against `lib` but contains
 ### UI
 
 - REQ-BAL-UI-WINDOW: On startup the tool displays a window containing a dynamically generated vertical list of arena buttons, one per arena defined in `balancing.toml`.
-- REQ-BAL-UI-BUTTON: Each arena button displays the arena name and two columns (one per team). Each column shows the team name as a header, followed by a list of entries. The HQ is always the first entry in each column. Below the HQ, ship types are listed, followed by defence stations (if any). Each entry uses the format `surviving/total TypeName Llevel` — for example `2/3 Fighter L5` or `1/1 HQ L1`. The surviving count updates live as the simulation progresses.
+- REQ-BAL-UI-BUTTON: Each arena button displays the arena name and two columns (one per team). Each column shows the team name as a header, followed by a list of entries. The HQ is always the first entry in each column. Below the HQ, ship types are listed, followed by defence stations (if any). Each entry uses the format `surviving/total TypeName Llevel` — for example `2/3 Fighter L5` or `1/1 HQ L1`. The surviving count updates live as the simulation progresses. When the fight ends, the winning team's name header is prefixed with `[WON]`.
 - REQ-BAL-UI-BUTTON-BORDER: While an arena's simulation is running, the button border is blue. When the fight ends, the border changes to green.
diff --git a/src/balancing/ArenaButton.cpp b/src/balancing/ArenaButton.cpp
index 5578fb7..aae1b39 100644
--- a/src/balancing/ArenaButton.cpp
+++ b/src/balancing/ArenaButton.cpp
@@ -62,7 +62,14 @@ void ArenaButton::updateStatus(const ArenaStatus& status)
         QLabel* header = (ti == 0) ? m_team1Header : m_team2Header;
         QLabel* content = (ti == 0) ? m_team1Content : m_team2Content;
 
-        header->setText(QString::fromStdString(team.name));
+        if (status.finished && status.winnerTeam == ti)
+        {
+            header->setText("[WON] " + QString::fromStdString(team.name));
+        }
+        else
+        {
+            header->setText(QString::fromStdString(team.name));
+        }
 
         QString lines;
         for (const ArenaStatus::Entry& entry : team.entries)
diff --git a/src/balancing/ArenaSimulation.cpp b/src/balancing/ArenaSimulation.cpp
index 778a92d..d97a001 100644
--- a/src/balancing/ArenaSimulation.cpp
+++ b/src/balancing/ArenaSimulation.cpp
@@ -28,6 +28,7 @@ ArenaSimulation::ArenaSimulation(const GameConfig& gameConfig,
     , m_team1HqId(kInvalidEntityId)
     , m_team2HqId(kInvalidEntityId)
     , m_finished(false)
+    , m_winnerTeam(-1)
     , m_stopRequested(false)
 {
     m_buildingSystem = std::make_unique<BuildingSystem>(
@@ -333,6 +334,7 @@ void ArenaSimulation::tickDeaths()
     if (team1HqGone || team2HqGone)
     {
         m_finished = true;
+        m_winnerTeam = team1HqGone ? 1 : 0;
         updateStatus();
         return;
     }
@@ -355,6 +357,7 @@ void ArenaSimulation::tickDeaths()
     if (!team1HasShips || !team2HasShips)
     {
         m_finished = true;
+        m_winnerTeam = team1HasShips ? 0 : 1;
         updateStatus();
     }
 }
@@ -363,6 +366,7 @@ void ArenaSimulation::updateStatus()
 {
     ArenaStatus newStatus;
     newStatus.finished = m_finished;
+    newStatus.winnerTeam = m_winnerTeam;
 
     for (int ti = 0; ti < 2; ++ti)
     {
diff --git a/src/balancing/ArenaSimulation.h b/src/balancing/ArenaSimulation.h
index 445e4ac..d112476 100644
--- a/src/balancing/ArenaSimulation.h
+++ b/src/balancing/ArenaSimulation.h
@@ -37,6 +37,7 @@ struct ArenaStatus
 
     TeamStatus teams[2];
     bool finished = false;
+    int winnerTeam = -1;  // 0 or 1 when finished; -1 while running
 };
 
 class ArenaSimulation
@@ -77,6 +78,7 @@ private:
     EntityId m_team2HqId;
 
     bool m_finished;
+    int m_winnerTeam;
     std::atomic<bool> m_stopRequested;
 
     mutable std::mutex m_statusMutex;