diff --git a/tuner/tuner/libtuner.py b/tuner/tuner/libtuner.py
index dceb79b66..7377d6701 100644
--- a/tuner/tuner/libtuner.py
+++ b/tuner/tuner/libtuner.py
@@ -876,14 +876,14 @@ def is_valid_for_device(self, device_id: str) -> bool:
 
     def get_candidates_ordered_by_speedup(
         self, candidate_results: list[BenchmarkResult]
-    ) -> Union[list[BenchmarkResult], list[tuple[BenchmarkResult, float]]]:
+    ) -> list[tuple[BenchmarkResult, float]]:
         """
-        returns:
-        - `list[BenchmarkResult]` sorted by runtime if no valid baselines exist.
-        - `list[tuple[BenchmarkResult, float]]` sorted by speedup when baselines are available.
+        Returns a list of tuples (BenchmarkResult, speedup) sorted in ascending order based on speedup
+        or raw runtime.
 
-        If no valid baseline times are available across all devices, candidates are sorted
-        and returned based on their raw runtime in ascending order.
+        If no valid baseline times are available across all devices, candidates are sorted based on
+        their raw runtime in ascending order. A placeholder speedup value of 1.0 is assigned to each
+        candidate.
 
         If valid baseline times exist, speedup is defined as the ratio of the candidate's runtime to
         the average baseline time for the corresponding device as:
@@ -896,7 +896,10 @@ def get_candidates_ordered_by_speedup(
         if not self.is_valid():
             logging.warning("No valid baseline times available.")
             # Use the candidate time directly when no baselines are available.
-            return sorted(candidate_results, key=lambda candidate: candidate.time)
+            return sorted(
+                [(candidate, 1.0) for candidate in candidate_results],
+                key=lambda x: x[0].time,
+            )
 
         # Calculate the fallback baseline as the average of all valid times across devices.
         valid_baseline_times = [
@@ -1065,11 +1068,7 @@ def benchmark(
                 f"({percentage_of_baseline:.1f}% of baseline)"
             )
     else:
-        top_candiates = [
-            result if isinstance(result, BenchmarkResult) else result[0]
-            for result in top_candidates_with_speedup
-        ]
-        for candidate in top_candiates:
+        for candidate, _ in top_candidates_with_speedup:
             time_ms = candidate.time
             candidate_id = candidate.candidate_id
             top_candidate_ids.append(candidate_id)
diff --git a/tuner/tuner/libtuner_test.py b/tuner/tuner/libtuner_test.py
index e0e3f6ba0..bbca2d370 100644
--- a/tuner/tuner/libtuner_test.py
+++ b/tuner/tuner/libtuner_test.py
@@ -290,11 +290,14 @@ def test_baseline_result_handler_speedup():
     ]
 
     handler = libtuner.BaselineResultHandler()
-    all_candidates = handler.get_candidates_ordered_by_speedup(candidates)
-    assert all_candidates == [
-        candidates[1],
-        candidates[0],
-        candidates[2],
+    all_candidates_with_speedup = handler.get_candidates_ordered_by_speedup(candidates)
+    assert all_candidates_with_speedup == [
+        (candidates[1], 1.0),
+        (candidates[0], 1.0),
+        (candidates[2], 1.0),
+    ]
+    top_candidates_with_speedup = all_candidates_with_speedup[:2]
+    assert [candidate.candidate_id for candidate, _ in top_candidates_with_speedup] == [
+        6,
+        5,
     ]
-    top_candidates = all_candidates[:2]
-    assert [candidate.candidate_id for candidate in top_candidates] == [6, 5]