diff --git a/addons/crm/models/crm_team.py b/addons/crm/models/crm_team.py
index 60b5c3ed49c..652df523700 100644
--- a/addons/crm/models/crm_team.py
+++ b/addons/crm/models/crm_team.py
@@ -497,11 +497,12 @@ class Team(models.Model):
                     leads_assigned += lead
                     leads_done_ids.add(lead.id)
 
-        leads_assigned._handle_salesmen_assignment(user_ids=None, team_id=self.id)
+        duplicates_to_assign = self.env['crm.lead'].union(*leads_dups_dict.keys())
+        (leads_assigned | duplicates_to_assign)._handle_salesmen_assignment(user_ids=None, team_id=self.id)
 
         for lead in leads.filtered(lambda lead: lead in leads_dups_dict):
             lead_duplicates = leads_dups_dict[lead]
-            merged = lead_duplicates._merge_opportunity(user_id=False, team_id=self.id, max_length=0)
+            merged = lead_duplicates._merge_opportunity(user_id=False, team_id=False, max_length=0)
             leads_dup_ids.update((lead_duplicates - merged).ids)
             leads_merged_ids.add(merged.id)
 
diff --git a/addons/crm/tests/test_crm_lead_assignment.py b/addons/crm/tests/test_crm_lead_assignment.py
index 11a5c953176..b72e8c19e64 100644
--- a/addons/crm/tests/test_crm_lead_assignment.py
+++ b/addons/crm/tests/test_crm_lead_assignment.py
@@ -196,6 +196,8 @@ class TestLeadAssign(TestLeadAssignCommon):
             self.env['crm.team'].browse(self.sales_teams.ids)._action_assign_leads(work_days=2)
 
         # teams assign
+        # due to duplicate management keeping master team, we may not ensure leads to be
+        # fulfilling their original team volume
         leads = self.env['crm.lead'].search([('id', 'in', leads.ids)])  # ensure order
         leads_st1 = leads.filtered_domain([('team_id', '=', self.sales_team_1.id)])
         leads_stc = leads.filtered_domain([('team_id', '=', self.sales_team_convert.id)])
@@ -411,5 +413,5 @@ class TestLeadAssign(TestLeadAssignCommon):
 
         sales_team_dupe._action_assign_leads(work_days=2)
         self.assertFalse(dupe_lead.exists())
-        self.assertEqual(master_opp.team_id, sales_team_dupe, 'Opportunity: current team wins lead even if was on duplicated lead')
+        self.assertEqual(master_opp.team_id, self.sales_team_1, 'Opportunity: should keep its sales team')
         self.assertEqual(master_opp.user_id, self.user_sales_manager, 'Opportunity: should keep its salesman')
diff --git a/addons/crm/tests/test_performances.py b/addons/crm/tests/test_performances.py
index fdea9cd00b6..42de8145b7b 100644
--- a/addons/crm/tests/test_performances.py
+++ b/addons/crm/tests/test_performances.py
@@ -54,6 +54,8 @@ class TestLeadAssignPerf(TestLeadAssignCommon):
                 self.env['crm.team'].browse(self.sales_teams.ids)._action_assign_leads(work_days=2)
 
         # teams assign
+        # due to duplicate management keeping master team, we may not ensure leads to be
+        # fulfilling their original team volume
         leads = self.env['crm.lead'].search([('id', 'in', leads.ids)])  # ensure order
         leads_st1 = leads.filtered_domain([('team_id', '=', self.sales_team_1.id)])
         leads_stc = leads.filtered_domain([('team_id', '=', self.sales_team_convert.id)])