diff --git a/constitution.py b/constitution.py
index d4ace9591f035d67721178a7c17e6053039800d1..7b7a61de87f7872ff9c66755200cf5103920eec6 100644
--- a/constitution.py
+++ b/constitution.py
@@ -1238,6 +1238,9 @@ async def pairwise_rank(n: int, compare_fn, progress_fn=None) -> list:
         results = await compare_fn(i, j)
         pairs.extend(results)
         compared.add(frozenset((i, j)))
+        # Resumed comparisons may be satisfied entirely from RocksDB without
+        # an I/O await. Yield explicitly so ranking never starves HTTP/SSE.
+        await asyncio.sleep(0)
         return results
 
     # --- Phase 1: spanning tree ---
diff --git a/tests/test_pair_selection.py b/tests/test_pair_selection.py
index 13040ef4a6789ef74e7449e8a39df3b67d1c2e8c..8a5614da2ba6062af961f2bb942af70fd7c69813 100644
--- a/tests/test_pair_selection.py
+++ b/tests/test_pair_selection.py
@@ -329,6 +329,30 @@ def test_progress_no_duplicate_spanning_steps():
     assert spanning_steps == sorted(set(spanning_steps))
 
 
+def test_cached_comparisons_yield_to_other_event_loop_work():
+    async def scenario():
+        heartbeat_ticks = 0
+        ranking_done = False
+
+        async def cached_compare(i, j):
+            # Deliberately contains no await, matching a RocksDB cache hit.
+            return [(min(i, j), max(i, j), 2.0, 1.0)]
+
+        async def heartbeat():
+            nonlocal heartbeat_ticks
+            while not ranking_done:
+                heartbeat_ticks += 1
+                await asyncio.sleep(0)
+
+        heartbeat_task = asyncio.create_task(heartbeat())
+        await pairwise_rank(20, cached_compare)
+        ranking_done = True
+        await heartbeat_task
+        return heartbeat_ticks
+
+    assert run(scenario()) >= 19
+
+
 # ---------------------------------------------------------------------------
 # rank_centrality accumulates (no overwrite bug)
 # ---------------------------------------------------------------------------