diff --git a/front/src/applications/operationalStudies/views/Scenario/components/SimulationResults/SimulationResults.tsx b/front/src/applications/operationalStudies/views/Scenario/components/SimulationResults/SimulationResults.tsx
index b214dd9233a..1d5176aea5f 100644
--- a/front/src/applications/operationalStudies/views/Scenario/components/SimulationResults/SimulationResults.tsx
+++ b/front/src/applications/operationalStudies/views/Scenario/components/SimulationResults/SimulationResults.tsx
@@ -117,6 +117,7 @@ const SimulationResults = ({
     timetableId,
     pathfinding: projectionData?.pathfinding,
     projectedOperationalPoints: projectionData?.operationalPoints,
+    operationalPointReferences: projectionData?.operationalPointReferences,
   });
 
   const {
diff --git a/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useGetProjectedTrainOperationalPoints.ts b/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useGetProjectedTrainOperationalPoints.ts
index 6c7131686fe..7997244928c 100644
--- a/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useGetProjectedTrainOperationalPoints.ts
+++ b/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useGetProjectedTrainOperationalPoints.ts
@@ -7,6 +7,7 @@ import { useSelector } from 'react-redux';
 import { upsertMapWaypointsInOperationalPoints } from 'applications/operationalStudies/helpers/upsertMapWaypointsInOperationalPoints';
 import type {
   CorePathfindingResultSuccess,
+  OperationalPointReference,
   TrainScheduleResponse,
 } from 'common/api/osrdEditoastApi';
 import { isStation } from 'modules/pathfinding/utils';
@@ -14,18 +15,32 @@ import type { PathOperationalPoint, ProjectionData } from 'modules/simulationRes
 import { getProjectionType } from 'reducers/simulationResults/selectors';
 
 import { getWaypointsLocalStorageKey } from './helpers/utils';
+
+function buildOpRefByPosition(
+  path: TrainScheduleResponse['path'],
+  pathfinding: CorePathfindingResultSuccess
+): Map<number, OperationalPointReference> {
+  const mapOpRef = new Map<number, OperationalPointReference>();
+  path.forEach((step, i) => {
+    if (step.location.type === 'operational_point_part_reference') {
+      mapOpRef.set(pathfinding.path_item_positions[i], step.location.operational_point);
+    }
+  });
+  return mapOpRef;
+}
+
 const useGetProjectedTrainOperationalPoints = ({
-  infraId,
   timetableId,
   path,
   pathfinding,
   projectedOperationalPoints,
+  operationalPointReferences,
 }: {
-  infraId: number;
   timetableId: number | undefined;
   path?: TrainScheduleResponse['path'];
   pathfinding?: CorePathfindingResultSuccess;
   projectedOperationalPoints?: ProjectionData['operationalPoints'];
+  operationalPointReferences?: OperationalPointReference[];
 }) => {
   const { t } = useTranslation('operational-studies');
   const projectionType = useSelector(getProjectionType);
@@ -35,54 +50,70 @@ const useGetProjectedTrainOperationalPoints = ({
     useState<PathOperationalPoint[]>(operationalPoints);
 
   useEffect(() => {
-    const getOperationalPoints = async () => {
-      let operationalPointsWithUniqueIds: PathOperationalPoint[] =
-        projectedOperationalPoints?.map((op, i) => ({
-          ...omit(op, 'id'),
-          waypointId: `${op.id}-${op.position}-${i}`,
-          opId: op.id,
-        })) || [];
-
-      operationalPointsWithUniqueIds =
-        projectionType === 'trackProjection' && path && pathfinding
-          ? upsertMapWaypointsInOperationalPoints(
-              'PathOperationalPoint',
-              path,
-              pathfinding.path_item_positions,
-              operationalPointsWithUniqueIds,
-              t
-            )
-          : operationalPointsWithUniqueIds;
-
-      setOperationalPoints(operationalPointsWithUniqueIds);
-
-      const stringifiedSavedWaypoints = localStorage.getItem(
-        getWaypointsLocalStorageKey(timetableId, path)
-      );
-
-      if (stringifiedSavedWaypoints) {
-        operationalPointsWithUniqueIds = JSON.parse(
-          stringifiedSavedWaypoints
-        ) as PathOperationalPoint[];
-      } else {
-        // If the manchette hasn't been saved, we want to display by default only
-        // the waypoints with CH BV/00/'' and the path steps (origin, destination, vias)
-
-        const lastIndex = operationalPointsWithUniqueIds.length - 1;
-        operationalPointsWithUniqueIds = operationalPointsWithUniqueIds.filter((op, i) => {
-          if (i === 0 || i === lastIndex) return true;
-          // handle waypoints added from the map
-          if (!op.extensions?.sncf) return true;
-          // handle waypoints added from the pathfinding or operational points on path
-          return isStation(op.extensions.sncf.ch) || op.weight === 100;
-        });
-      }
-
-      setFilteredOperationalPoints(operationalPointsWithUniqueIds);
-    };
-
-    getOperationalPoints();
-  }, [path, pathfinding, infraId, projectedOperationalPoints, timetableId, t, projectionType]);
+    // Successful pathfinding: position → original OP reference for path steps.
+    // Failed pathfinding: pathfinding is undefined, map stays null (index-based fallback below).
+    const opRefByPosition = path && pathfinding ? buildOpRefByPosition(path, pathfinding) : null;
+
+    const baseOps: PathOperationalPoint[] =
+      projectedOperationalPoints?.map((op, i) => ({
+        ...omit(op, 'id'),
+        waypointId: `${op.id}-${op.position}-${i}`,
+        opId: op.id,
+        // Successful pathfinding: match by position against path steps.
+        // Failed pathfinding: operationalPointReferences[i] is the original opRef for projectedOperationalPoints[i].
+        opRef: opRefByPosition ? opRefByPosition.get(op.position) : operationalPointReferences?.[i],
+      })) || [];
+
+    const operationalPointsWithUniqueIds =
+      projectionType === 'trackProjection' && path && pathfinding
+        ? upsertMapWaypointsInOperationalPoints(
+            'PathOperationalPoint',
+            path,
+            pathfinding.path_item_positions,
+            baseOps,
+            t
+          )
+        : baseOps;
+
+    setOperationalPoints(operationalPointsWithUniqueIds);
+
+    const opRefByWaypointId = new Map(
+      operationalPointsWithUniqueIds.map((op) => [op.waypointId, op.opRef])
+    );
+
+    const stringifiedSavedWaypoints = localStorage.getItem(
+      getWaypointsLocalStorageKey(timetableId, path)
+    );
+
+    let filteredOps: PathOperationalPoint[];
+    if (stringifiedSavedWaypoints) {
+      filteredOps = (JSON.parse(stringifiedSavedWaypoints) as PathOperationalPoint[]).map((op) => ({
+        ...op,
+        opRef: opRefByWaypointId.get(op.waypointId),
+      }));
+    } else {
+      // If the manchette hasn't been saved, we want to display by default only
+      // the waypoints with CH BV/00/'' and the path steps (origin, destination, vias)
+      const lastIndex = operationalPointsWithUniqueIds.length - 1;
+      filteredOps = operationalPointsWithUniqueIds.filter((op, i) => {
+        if (i === 0 || i === lastIndex) return true;
+        // handle waypoints added from the map
+        if (!op.extensions?.sncf) return true;
+        // handle waypoints added from the pathfinding or operational points on path
+        return isStation(op.extensions.sncf.ch) || op.weight === 100;
+      });
+    }
+
+    setFilteredOperationalPoints(filteredOps);
+  }, [
+    path,
+    pathfinding,
+    projectedOperationalPoints,
+    operationalPointReferences,
+    timetableId,
+    t,
+    projectionType,
+  ]);
 
   return { operationalPoints, filteredOperationalPoints, setFilteredOperationalPoints };
 };
diff --git a/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useTrackOccupancy.ts b/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useTrackOccupancy.ts
index aff379b47ad..89ce37335c2 100644
--- a/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useTrackOccupancy.ts
+++ b/front/src/modules/simulationResult/components/SpaceTimeChartWrapper/useTrackOccupancy.ts
@@ -58,6 +58,7 @@ function getOperationalPointReference(
   op: PathOperationalPoint | undefined
 ): OperationalPointReference | undefined {
   if (!op) return undefined;
+  if (op.opRef) return op.opRef;
   // Only use the opId when it refers to a real infra OP. Virtual OPs (unrecognised, created
   // by usePathProjection when pathfinding fails) have a synthetic id like "virtual_op_Zürich"
   // and an empty part.track — they must be matched by trigram/uic instead.
diff --git a/front/src/modules/simulationResult/types.ts b/front/src/modules/simulationResult/types.ts
index 35d9207880f..a6e94a26fe6 100644
--- a/front/src/modules/simulationResult/types.ts
+++ b/front/src/modules/simulationResult/types.ts
@@ -9,6 +9,7 @@ import type {
 import type {
   PacedTrainException,
   CoreSignalUpdate,
+  OperationalPointReference,
   PathProperties,
   RollingStockWithLiveries,
   SimulationResponseSuccess,
@@ -30,6 +31,7 @@ export type EditoastPathOperationalPoint = NonNullable<
 export type PathOperationalPoint = Omit<EditoastPathOperationalPoint, 'id'> & {
   waypointId: string;
   opId: string | null;
+  opRef?: OperationalPointReference;
 };
 
 // Space Time Chart