diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index d2766cd6d..65d9909c6 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -2420,7 +2420,7 @@ class Exchange:
         :param mark_rates: Dataframe containing Mark rates (Type mark_ohlcv_price)
         """
 
-        return funding_rates.merge(mark_rates, on='date', how="inner", suffixes=["_fund", "_mark"])
+        return mark_rates.merge(funding_rates, on='date', how="inner", suffixes=["_mark", "_fund"])
 
     def calculate_funding_fees(
         self,
diff --git a/freqtrade/optimize/backtesting.py b/freqtrade/optimize/backtesting.py
index 99bddbf8a..3041136a3 100755
--- a/freqtrade/optimize/backtesting.py
+++ b/freqtrade/optimize/backtesting.py
@@ -296,9 +296,10 @@ class Backtesting:
                             how="outer", suffixes=["_mark", "_fund"])['open_fund'].fillna(
                                 self.config.get('futures_funding_rate'))
                     else:
-                        self.futures_data[pair] = mark_rates_dict[pair].merge(
-                            funding_rates_dict[pair], on='date',
-                            how="inner", suffixes=["_mark", "_fund"])
+                        self.futures_data[pair] = self.exchange.combine_funding_and_mark(
+                            funding_rates=funding_rates_dict[pair],
+                            mark_rates=mark_rates_dict[pair]
+                        )
 
             if unavailable_pairs:
                 raise OperationalException(