diff --git a/client/trino-client/src/main/java/io/trino/client/JsonIterators.java b/client/trino-client/src/main/java/io/trino/client/JsonIterators.java
index dc7b3e4f146f..c992fde32dbf 100644
--- a/client/trino-client/src/main/java/io/trino/client/JsonIterators.java
+++ b/client/trino-client/src/main/java/io/trino/client/JsonIterators.java
@@ -26,7 +26,6 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.UncheckedIOException;
-import java.util.ArrayList;
 import java.util.List;
 
 import static com.fasterxml.jackson.core.JsonParser.Feature.AUTO_CLOSE_SOURCE;
@@ -36,7 +35,6 @@
 import static com.fasterxml.jackson.core.JsonToken.START_ARRAY;
 import static com.google.common.base.Verify.verify;
 import static io.trino.client.JsonDecodingUtils.createTypeDecoders;
-import static java.util.Collections.unmodifiableList;
 import static java.util.Objects.requireNonNull;
 
 public final class JsonIterators
@@ -112,17 +110,14 @@ public List<Object> computeNext()
                 return endOfData();
             }
             try {
-                List<Object> row = new ArrayList<>(decoders.length);
-                for (TypeDecoder decoder : decoders) {
-                    if (requireNonNull(parser.nextToken()) == JsonToken.VALUE_NULL) {
-                        row.add(null);
-                    }
-                    else {
-                        row.add(decoder.decode(parser)); // allow nulls
+                Object[] row = new Object[decoders.length];
+                for (int i = 0; i < decoders.length; i++) {
+                    if (requireNonNull(parser.nextToken()) != JsonToken.VALUE_NULL) {
+                        row[i] = decoders[i].decode(parser); // allow nulls
                     }
                 }
                 checkIfClosed();
-                return unmodifiableList(row);
+                return List.of(row);
             }
             catch (IOException e) {
                 throw new UncheckedIOException(e);