diff --git a/server/repository/repository_test.go b/server/repository/repository_test.go
index f4d80c3c434d8..91c2e016ab3d4 100644
--- a/server/repository/repository_test.go
+++ b/server/repository/repository_test.go
@@ -21,6 +21,7 @@ import (
 
 	"github.com/argoproj/argo-cd/v2/common"
 	"github.com/argoproj/argo-cd/v2/pkg/apiclient/repository"
+	repositorypkg "github.com/argoproj/argo-cd/v2/pkg/apiclient/repository"
 	appsv1 "github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
 	fakeapps "github.com/argoproj/argo-cd/v2/pkg/client/clientset/versioned/fake"
 	appinformer "github.com/argoproj/argo-cd/v2/pkg/client/informers/externalversions"
@@ -1119,3 +1120,35 @@ func TestGetRepository(t *testing.T) {
 		})
 	}
 }
+
+func TestDeleteRepository(t *testing.T) {
+	repositories := map[string]string{
+		"valid": "https://bitbucket.org/workspace/repo.git",
+		// Check a wrongly formatter repo as well, see https://github.com/argoproj/argo-cd/issues/20921
+		"invalid": "git clone https://bitbucket.org/workspace/repo.git",
+	}
+
+	kubeclientset := fake.NewSimpleClientset(&argocdCM, &argocdSecret)
+	settingsMgr := settings.NewSettingsManager(context.Background(), kubeclientset, testNamespace)
+
+	for name, repo := range repositories {
+		t.Run(name, func(t *testing.T) {
+			repoServerClient := mocks.RepoServerServiceClient{}
+			repoServerClient.On("TestRepository", mock.Anything, mock.Anything).Return(&apiclient.TestRepositoryResponse{}, nil)
+
+			repoServerClientset := mocks.Clientset{RepoServerServiceClient: &repoServerClient}
+			enforcer := newEnforcer(kubeclientset)
+
+			db := &dbmocks.ArgoDB{}
+			db.On("DeleteRepository", context.TODO(), repo, "default").Return(nil)
+			db.On("ListRepositories", context.TODO()).Return([]*appsv1.Repository{{Repo: repo, Project: "default"}}, nil)
+			db.On("GetRepository", context.TODO(), repo, "default").Return(&appsv1.Repository{Repo: repo, Project: "default"}, nil)
+			appLister, projLister := newAppAndProjLister(defaultProj)
+
+			s := NewServer(&repoServerClientset, db, enforcer, newFixtures().Cache, appLister, projLister, testNamespace, settingsMgr)
+			resp, err := s.DeleteRepository(context.TODO(), &repository.RepoQuery{Repo: repo, AppProject: "default"})
+			require.NoError(t, err)
+			assert.Equal(t, repositorypkg.RepoResponse{}, *resp)
+		})
+	}
+}
diff --git a/util/git/git.go b/util/git/git.go
index 3a087aeb00096..6ef47fecfb172 100644
--- a/util/git/git.go
+++ b/util/git/git.go
@@ -35,8 +35,8 @@ func IsTruncatedCommitSHA(sha string) bool {
 
 // SameURL returns whether or not the two repository URLs are equivalent in location
 func SameURL(leftRepo, rightRepo string) bool {
-	normalLeft := NormalizeGitURL(leftRepo)
-	normalRight := NormalizeGitURL(rightRepo)
+	normalLeft := NormalizeGitURLAllowInvalid(leftRepo)
+	normalRight := NormalizeGitURLAllowInvalid(rightRepo)
 	return normalLeft != "" && normalRight != "" && normalLeft == normalRight
 }
 
@@ -45,6 +45,16 @@ func SameURL(leftRepo, rightRepo string) bool {
 // Prefer using SameURL() over this function when possible. This algorithm may change over time
 // and should not be considered stable from release to release
 func NormalizeGitURL(repo string) string {
+	return normalizeGitURL(repo, false)
+}
+
+// Similar to NormalizeGitURL, except returning a not fully normalized string when the url is invalid.
+// Needed to allow a deletion of repos with invalid urls. See https://github.com/argoproj/argo-cd/issues/20921.
+func NormalizeGitURLAllowInvalid(repo string) string {
+	return normalizeGitURL(repo, true)
+}
+
+func normalizeGitURL(repo string, allowInvalid bool) string {
 	repo = strings.ToLower(strings.TrimSpace(repo))
 	if yes, _ := IsSSHURL(repo); yes {
 		if !strings.HasPrefix(repo, "ssh://") {
@@ -57,7 +67,11 @@ func NormalizeGitURL(repo string) string {
 	repo = strings.TrimSuffix(repo, ".git")
 	repoURL, err := url.Parse(repo)
 	if err != nil {
-		return ""
+		if allowInvalid {
+			return repo
+		} else {
+			return ""
+		}
 	}
 	normalized := repoURL.String()
 	return strings.TrimPrefix(normalized, "ssh://")