diff --git a/src/handler/manager/getTournaments.ts b/src/handler/manager/getTournaments.ts
index 3d0459f..2e562d5 100644
--- a/src/handler/manager/getTournaments.ts
+++ b/src/handler/manager/getTournaments.ts
@@ -5,7 +5,7 @@ import { AuthenticatedRequest } from "../../lib/middleware/requireAuth.js";
 
 export const getTournaments = async (
   req: AuthenticatedRequest,
-  res: Response,
+  res: Response
 ): Promise<void> => {
   try {
     let rows = await prismaClient.tournament.findMany({
@@ -213,6 +213,7 @@ export const getTournaments = async (
     } else {
       count = (await prismaClient.tournament.findMany({})).length;
     }
+    let teamTournamentKeys = new Set<string>();
     if (req.user.teamNumber) {
       const teamTournaments = await prismaClient.teamMatchData.groupBy({
         by: ["tournamentKey"],
@@ -220,9 +221,12 @@ export const getTournaments = async (
           teamNumber: req.user.teamNumber,
         },
       });
+      teamTournamentKeys = new Set(
+        teamTournaments.map((obj) => obj.tournamentKey)
+      );
       const presentTeamTournaments = [];
       for (let i = 0; i < rows.length; i++) {
-        if (teamTournaments.some((obj) => obj.tournamentKey === rows[i].key)) {
+        if (teamTournamentKeys.has(rows[i].key)) {
           presentTeamTournaments.push(rows[i]);
           rows.splice(i, 1);
           i--;
@@ -230,6 +234,12 @@ export const getTournaments = async (
       }
       rows = presentTeamTournaments.concat(rows);
     }
+
+    rows = rows.map((row) => ({
+      ...row,
+      isParticipant: teamTournamentKeys.has(row.key),
+    }));
+
     res.status(200).send({ tournaments: rows, count: count });
   } catch (error) {
     console.error(error);