diff --git a/frontend/src/App.jsx b/frontend/src/App.jsx
index df31d12..e1e0072 100644
--- a/frontend/src/App.jsx
+++ b/frontend/src/App.jsx
@@ -5409,6 +5409,35 @@ function TournamentMatchList({ sides, navigate }) {
   )
 }
 
+// Swiss tournaments often have round: null on every match because the bot doesn't
+// populate that field. Matches ARE returned in round order (sorted by time_start /
+// match_id), so we can infer round boundaries: floor(uniqueTeams / 2) matches per
+// round. Only kicks in when a list side has exactly one column (all-null rounds).
+function inferSwissRounds(sides) {
+  return sides.map((side) => {
+    if (side.kind !== 'list' || side.columns.length !== 1) return side
+    const allMatches = side.columns[0].matches
+    if (!allMatches.length) return side
+    const teams = new Set()
+    allMatches.forEach((m) => {
+      if (m.team_a_name) teams.add(m.team_a_name)
+      if (m.team_b_name) teams.add(m.team_b_name)
+    })
+    const matchesPerRound = Math.floor(teams.size / 2)
+    if (matchesPerRound <= 0 || allMatches.length <= matchesPerRound) return side
+    const columns = []
+    for (let i = 0; i < allMatches.length; i += matchesPerRound) {
+      const roundNum = columns.length + 1
+      columns.push({
+        id: `${side.key}:inferred:${roundNum}`,
+        label: `Round ${roundNum}`,
+        matches: allMatches.slice(i, i + matchesPerRound),
+      })
+    }
+    return { ...side, columns }
+  })
+}
+
 function TournamentDetailPage({ tournamentId, navigate }) {
   const [state, setState] = useState({ status: 'loading', data: null, error: null })
 
@@ -5431,7 +5460,10 @@ function TournamentDetailPage({ tournamentId, navigate }) {
   const data = state.data
   const matches = useMemo(() => data?.matches || [], [data])
   const format = useMemo(() => tournamentFormatMeta(data?.format, matches), [data?.format, matches])
-  const { sides } = useMemo(() => buildBracket(matches), [matches])
+  const { sides } = useMemo(() => {
+    const result = buildBracket(matches)
+    return { ...result, sides: inferSwissRounds(result.sides) }
+  }, [matches])
   const bracketSides = sides.filter((side) => side.kind === 'bracket')
   const listSides = sides.filter((side) => side.kind === 'list')
   const standings = data?.standings || []