diff --git a/src/main/java/it/cavallium/dbengine/client/LuceneIndexImpl.java b/src/main/java/it/cavallium/dbengine/client/LuceneIndexImpl.java
index a9d82af..b242a9b 100644
--- a/src/main/java/it/cavallium/dbengine/client/LuceneIndexImpl.java
+++ b/src/main/java/it/cavallium/dbengine/client/LuceneIndexImpl.java
@@ -86,7 +86,7 @@ public class LuceneIndexImpl<T, U> implements LuceneIndex<T, U> {
 
 	private Mono<SearchResultKeys<T>> transformLuceneResultWithTransformer(LLSearchResultShard llSearchResult) {
 		return Mono.just(new SearchResultKeys<>(llSearchResult.results()
-				.map(signal -> new SearchResultKey<>(signal.key().map(indicizer::getKey), signal.score())),
+				.map(signal -> new SearchResultKey<>(Mono.fromCallable(signal::key).map(indicizer::getKey), signal.score())),
 				llSearchResult.totalHitsCount(),
 				llSearchResult.release()
 		));
@@ -95,7 +95,7 @@ public class LuceneIndexImpl<T, U> implements LuceneIndex<T, U> {
 	private Mono<SearchResult<T, U>> transformLuceneResultWithValues(LLSearchResultShard llSearchResult,
 			ValueGetter<T, U> valueGetter) {
 		return Mono.fromCallable(() -> new SearchResult<>(llSearchResult.results().map(signal -> {
-			var key = signal.key().map(indicizer::getKey);
+			var key = Mono.fromCallable(signal::key).map(indicizer::getKey);
 			return new SearchResultItem<>(key, key.flatMap(valueGetter::get), signal.score());
 		}), llSearchResult.totalHitsCount(), llSearchResult.release()));
 	}
@@ -104,7 +104,11 @@ public class LuceneIndexImpl<T, U> implements LuceneIndex<T, U> {
 			ValueTransformer<T, U> valueTransformer) {
 		var scoresWithKeysFlux = llSearchResult
 				.results()
-				.flatMapSequential(signal -> signal.key().map(indicizer::getKey).map(key -> Tuples.of(signal.score(), key)));
+				.flatMapSequential(signal -> Mono
+						.fromCallable(signal::key)
+						.map(indicizer::getKey)
+						.map(key -> Tuples.of(signal.score(), key))
+				);
 		var resultItemsFlux = valueTransformer
 				.transform(scoresWithKeysFlux)
 				.filter(tuple3 -> tuple3.getT3().isPresent())
diff --git a/src/main/java/it/cavallium/dbengine/database/LLKeyScore.java b/src/main/java/it/cavallium/dbengine/database/LLKeyScore.java
index 0c0d28e..770c11d 100644
--- a/src/main/java/it/cavallium/dbengine/database/LLKeyScore.java
+++ b/src/main/java/it/cavallium/dbengine/database/LLKeyScore.java
@@ -2,32 +2,7 @@ package it.cavallium.dbengine.database;
 
 import java.util.Objects;
 import java.util.StringJoiner;
+import org.jetbrains.annotations.Nullable;
 import reactor.core.publisher.Mono;
 
-public record LLKeyScore(int docId, float score, Mono<String> key) {
-
-	@Override
-	public boolean equals(Object o) {
-		if (this == o) {
-			return true;
-		}
-		if (o == null || getClass() != o.getClass()) {
-			return false;
-		}
-		LLKeyScore that = (LLKeyScore) o;
-		return docId == that.docId && Float.compare(that.score, score) == 0;
-	}
-
-	@Override
-	public int hashCode() {
-		return Objects.hash(docId, score);
-	}
-
-	@Override
-	public String toString() {
-		return new StringJoiner(", ", LLKeyScore.class.getSimpleName() + "[", "]")
-				.add("docId=" + docId)
-				.add("score=" + score)
-				.toString();
-	}
-}
+public record LLKeyScore(int docId, float score, @Nullable String key) {}
diff --git a/src/main/java/it/cavallium/dbengine/lucene/LuceneUtils.java b/src/main/java/it/cavallium/dbengine/lucene/LuceneUtils.java
index fd06fd4..123ad78 100644
--- a/src/main/java/it/cavallium/dbengine/lucene/LuceneUtils.java
+++ b/src/main/java/it/cavallium/dbengine/lucene/LuceneUtils.java
@@ -370,7 +370,7 @@ public class LuceneUtils {
 								.map(hit -> {
 									var result = mapHitBlocking(hit, indexSearchers, keyFieldName);
 									// The "else" value is an errored key score, to filter out next
-									return Objects.requireNonNullElseGet(result, () -> new LLKeyScore(-1, -1, Mono.empty()));
+									return Objects.requireNonNullElseGet(result, () -> new LLKeyScore(-1, -1, null));
 								})
 								.sequential()
 								// Filter out the errored key scores
@@ -389,12 +389,13 @@ public class LuceneUtils {
 		var indexSearcher = indexSearchers.shard(shardIndex);
 		try {
 			String collectedDoc = keyOfTopDoc(shardDocId, indexSearcher.getIndexReader(), keyFieldName);
-			return new LLKeyScore(shardDocId, score, Mono.just(collectedDoc));
+			return new LLKeyScore(shardDocId, score, collectedDoc);
 		} catch (NoSuchElementException ex) {
-			logger.debug("Error: document " + shardDocId + " key is not present!");
+			logger.debug("Error: document {} key is not present!", shardDocId);
 			return null;
 		} catch (Exception ex) {
-			return new LLKeyScore(shardDocId, score, Mono.error(ex));
+			logger.error("Failed to read document {}", shardDocId, ex);
+			return new LLKeyScore(shardDocId, score, null);
 		}
 	}