Expose wrapped scorer in ProfileScorer via getWrappedScorer method

CHANGELOG.md

@@ -5,6 +5,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased 3.x]
 ### Added
+- Add getWrappedScorer method to ProfileScorer for plugin access to wrapped scorers ([#20548](https://github.com/opensearch-project/OpenSearch/issues/20548))
 - Support expected cluster name with validation in CCS Sniff mode ([#20532](https://github.com/opensearch-project/OpenSearch/pull/20532))
 
 ### Changed

server/src/main/java/org/opensearch/search/profile/query/ProfileScorer.java

@@ -65,6 +65,26 @@ final class ProfileScorer extends Scorer {
         setMinCompetitiveScoreTimer = profile.getTimer(QueryTimingType.SET_MIN_COMPETITIVE_SCORE);
     }
 
+    /**
+     * Returns the wrapped scorer.
+     * <p>
+     * This is useful for plugin queries that extend the Scorer API with custom methods not part of the standard
+     * Lucene Scorer interface. For example, neural-search's HybridQuery needs to access its HybridBulkScorer
+     * to call custom methods when profiling is enabled.
+     * </p>
+     * <p>
+     * <b>Note:</b> Calling mutation methods (like {@link #setMinCompetitiveScore(float)}) directly on the
+     * wrapped scorer will bypass profiling instrumentation for those calls. For read-only access or accessing
+     * custom methods not part of the standard Scorer API, this is safe and expected.
+     * </p>
+     *
+     * @return the underlying wrapped scorer
+     * @see ProfileCollector#getDelegate()
+     */
+    public Scorer getWrappedScorer() {
+        return scorer;
+    }
+
     @Override
     public int docID() {
         return scorer.docID();

server/src/test/java/org/opensearch/search/profile/query/ProfileScorerTests.java

@@ -101,4 +101,15 @@ public void testPropagateMaxScore() throws IOException {
         fakeScorer.maxScore = 42f;
         assertEquals(42f, profileScorer.getMaxScore(DocIdSetIterator.NO_MORE_DOCS), 0f);
     }
+
+    public void testGetWrappedScorer() throws IOException {
+        Query query = new MatchAllDocsQuery();
+        Weight weight = query.createWeight(new IndexSearcher(new MultiReader()), ScoreMode.TOP_SCORES, 1f);
+        FakeScorer fakeScorer = new FakeScorer(weight);
+        QueryProfileBreakdown profile = new QueryProfileBreakdown(ProfileMetricUtil.getDefaultQueryProfileMetrics());
+        ProfileScorer profileScorer = new ProfileScorer(fakeScorer, profile);
+
+        // Verify getWrappedScorer returns the original scorer
+        assertSame(fakeScorer, profileScorer.getWrappedScorer());
+    }
 }