diff --git a/server/src/lib/imports/imports.ts b/server/src/lib/imports/imports.ts
index e7f49d263..c7cc5bd33 100644
--- a/server/src/lib/imports/imports.ts
+++ b/server/src/lib/imports/imports.ts
@@ -1,10 +1,18 @@
 import db from "external/mongo/db";
 import CreateLogCtx from "lib/logger/logger";
+import {
+	CheckAndSetOngoingImportLock,
+	UnsetOngoingImportLock,
+} from "lib/score-import/framework/import-locks/lock";
 import { DeleteMultipleScores } from "lib/score-mutation/delete-scores";
 import type { ImportDocument } from "tachi-common";
 
 const logger = CreateLogCtx(__filename);
 
+interface OngoingImportError {
+	tag: "ONGOING_IMPORT";
+}
+
 /**
  * Given an importDocument, undo it. This will remove all of the scores inside the import.
  *
@@ -12,28 +20,46 @@ const logger = CreateLogCtx(__filename);
  *
  * If this results in sessions being deleted, it will delete them.
  */
-export async function RevertImport(importDoc: ImportDocument) {
+export async function RevertImport(importDoc: ImportDocument): Promise<OngoingImportError | null> {
 	logger.info(`Received revert-import request for import '${importDoc.importID}'`, { importDoc });
 
 	const scores = await GetImportScores(importDoc);
 
-	await DeleteMultipleScores(scores);
+	const hasNoOngoingImport = await CheckAndSetOngoingImportLock(importDoc.userID);
 
-	logger.info(
-		`Deleted ${scores.length} scores as part of reverting import '${importDoc.importID}'.`,
-		{ importDoc }
-	);
+	if (hasNoOngoingImport) {
+		logger.info(
+			`User ${importDoc.userID} tried to revert an import while they had one ongoing.`
+		);
+
+		return {
+			tag: "ONGOING_IMPORT",
+		};
+	}
 
 	try {
-		await db.imports.remove({ importID: importDoc.importID });
+		await DeleteMultipleScores(scores);
 
-		logger.info(`Reverted and deleted import '${importDoc.importID}'.`);
-	} catch (err) {
-		logger.severe(
-			`Deleted scores that were part of import, but failed to remove the actual import? There is a stale import with ID '${importDoc.importID}', which must be removed manually.`,
-			{ importDoc, err }
+		logger.info(
+			`Deleted ${scores.length} scores as part of reverting import '${importDoc.importID}'.`,
+			{ importDoc }
 		);
+
+		try {
+			await db.imports.remove({ importID: importDoc.importID });
+
+			logger.info(`Reverted and deleted import '${importDoc.importID}'.`);
+		} catch (err) {
+			logger.severe(
+				`Deleted scores that were part of import, but failed to remove the actual import? There is a stale import with ID '${importDoc.importID}', which must be removed manually.`,
+				{ importDoc, err }
+			);
+		}
+	} finally {
+		await UnsetOngoingImportLock(importDoc.userID);
 	}
+
+	return null;
 }
 
 /**
diff --git a/server/src/server/router/api/v1/imports/router.ts b/server/src/server/router/api/v1/imports/router.ts
index f2fb7a680..c9cba2b3d 100644
--- a/server/src/server/router/api/v1/imports/router.ts
+++ b/server/src/server/router/api/v1/imports/router.ts
@@ -183,7 +183,14 @@ router.post(
 	async (req, res) => {
 		const importDoc = GetTachiData(req, "importDoc");
 
-		await RevertImport(importDoc);
+		const k = await RevertImport(importDoc);
+
+		if (k !== null) {
+			return res.status(409).json({
+				success: false,
+				description: `You already have an import or a revert ongoing.`,
+			});
+		}
 
 		return res.status(200).json({
 			success: true,