diff --git a/lisa/trace.py b/lisa/trace.py
index bf0110ec5e73ebc4040cc76b936daa1b5f254744..678e93fc4d1bf261292de3b5788913c15037ef15 100644
--- a/lisa/trace.py
+++ b/lisa/trace.py
@@ -783,7 +783,7 @@ class MockTraceParser(TraceParserBase):
                 )
 
                 start, end = df.select(
-                    (pl.min('Time'), pl.max('Time'))
+                    (pl.min('Time').alias('min'), pl.max('Time').alias('max'))
                 ).collect().row(0)
 
                 start = Timestamp(start, unit='ns', rounding='down')