diff --git a/freqtrade/optimize/backtesting.py b/freqtrade/optimize/backtesting.py
index 2a96037ac..12536c333 100644
--- a/freqtrade/optimize/backtesting.py
+++ b/freqtrade/optimize/backtesting.py
@@ -24,6 +24,7 @@ from freqtrade.enums import (BacktestState, CandleType, ExitCheckTuple, ExitType
                              TradingMode)
 from freqtrade.exceptions import DependencyException, OperationalException
 from freqtrade.exchange import timeframe_to_minutes, timeframe_to_seconds
+from freqtrade.exchange.exchange import amount_to_precision
 from freqtrade.mixins import LoggingMixin
 from freqtrade.optimize.backtest_caching import get_strategy_run_id
 from freqtrade.optimize.bt_progress import BTProgress
@@ -822,8 +823,11 @@ class Backtesting:
             self.order_id_counter += 1
             base_currency = self.exchange.get_pair_base_currency(pair)
             amount_p = (stake_amount / propose_rate) * leverage
-            amount = self.exchange._contracts_to_amount(pair, self.exchange.amount_to_precision(
-                pair, self.exchange._amount_to_contracts(pair, amount_p)))
+            amount = self.exchange._contracts_to_amount(
+                pair, amount_to_precision(
+                    self.exchange._amount_to_contracts(pair, amount_p),
+                    self.exchange.get_precision_amount(pair), self.precision_mode)
+                )
             # Backcalculate actual stake amount.
             stake_amount = amount * propose_rate / leverage
 
diff --git a/tests/optimize/test_backtesting_adjust_position.py b/tests/optimize/test_backtesting_adjust_position.py
index 0cbad29f6..f0829ea1e 100644
--- a/tests/optimize/test_backtesting_adjust_position.py
+++ b/tests/optimize/test_backtesting_adjust_position.py
@@ -18,7 +18,7 @@ from tests.conftest import patch_exchange
 def test_backtest_position_adjustment(default_conf, fee, mocker, testdatadir) -> None:
     default_conf['use_exit_signal'] = False
     mocker.patch('freqtrade.exchange.Exchange.get_fee', fee)
-    mocker.patch('freqtrade.exchange.Exchange.amount_to_precision', lambda s, x, y: round(y, 8))
+    mocker.patch('freqtrade.optimize.backtesting.amount_to_precision', lambda x, y, z: round(x, 8))
     mocker.patch("freqtrade.exchange.Exchange.get_min_pair_stake_amount", return_value=0.00001)
     mocker.patch("freqtrade.exchange.Exchange.get_max_pair_stake_amount", return_value=float('inf'))
     patch_exchange(mocker)