diff --git a/erpnext/stock/doctype/material_request/material_request.py b/erpnext/stock/doctype/material_request/material_request.py
index a806b5b6a31..4faa24941a0 100644
--- a/erpnext/stock/doctype/material_request/material_request.py
+++ b/erpnext/stock/doctype/material_request/material_request.py
@@ -12,7 +12,7 @@ import frappe.defaults
 from frappe import _, msgprint
 from frappe.model.document import Document
 from frappe.query_builder import Order
-from frappe.query_builder.functions import Sum
+from frappe.query_builder.functions import Min, Sum
 from frappe.utils import cint, flt, get_datetime, get_link_to_form, getdate, new_line_sep, nowdate
 
 from erpnext.buying.utils import check_on_hold_or_closed_status, validate_for_items
@@ -483,9 +483,7 @@ def get_material_requests_based_on_supplier(
 	query = (
 		frappe.qb.from_(mr)
 		.from_(mr_item)
-		.select(mr.name)
-		.distinct()
-		.select(mr.transaction_date, mr.company)
+		.select(mr.name, mr.transaction_date, mr.company)
 		.where(
 			(mr.name == mr_item.parent)
 			& (mr_item.item_code.isin(supplier_items))
@@ -495,7 +493,8 @@ def get_material_requests_based_on_supplier(
 			& (mr.status != "Stopped")
 			& (mr.company == filters.get("company"))
 		)
-		.orderby(mr_item.item_code, order=Order.asc)
+		.groupby(mr.name, mr.transaction_date, mr.company)
+		.orderby(Min(mr_item.item_code), order=Order.asc)
 		.limit(cint(page_len))
 		.offset(cint(start))
 	)
diff --git a/erpnext/stock/doctype/material_request/test_material_request.py b/erpnext/stock/doctype/material_request/test_material_request.py
index 0e1c42c0828..c6e63269c1f 100644
--- a/erpnext/stock/doctype/material_request/test_material_request.py
+++ b/erpnext/stock/doctype/material_request/test_material_request.py
@@ -1252,6 +1252,44 @@ class TestMaterialRequest(ERPNextTestSuite):
 		over.items[0].qty = 4
 		over.validate_qty_against_so()
 
+	def test_get_material_requests_based_on_supplier(self):
+		"""The supplier-based Material Request picker must run on every engine.
+
+		It deduplicated requests with SELECT DISTINCT while ordering by an item
+		column that is not in the select list; PostgreSQL rejects that, so the
+		picker has to group and order by an aggregate instead.
+		"""
+		from erpnext.stock.doctype.material_request.material_request import (
+			get_material_requests_based_on_supplier,
+		)
+
+		item = create_item("_Test MR Default Supplier Item")
+		item.set("item_defaults", [])
+		item.append(
+			"item_defaults",
+			{
+				"company": "_Test Company",
+				"default_warehouse": "_Test Warehouse - _TC",
+				"default_supplier": "_Test Supplier",
+			},
+		)
+		item.save()
+
+		mr1 = make_material_request(item_code=item.name, qty=5)
+		mr2 = make_material_request(item_code=item.name, qty=7)
+
+		result = get_material_requests_based_on_supplier(
+			doctype="Material Request",
+			txt="",
+			searchfield="name",
+			start=0,
+			page_len=20,
+			filters={"supplier": "_Test Supplier", "company": "_Test Company"},
+		)
+		returned = {row["name"] for row in result}
+		self.assertIn(mr1.name, returned)
+		self.assertIn(mr2.name, returned)
+
 
 def get_in_transit_warehouse(company):
 	if not frappe.db.exists("Warehouse Type", "Transit"):