diff --git a/src/search.cpp b/src/search.cpp
index f1e75b0..40eab05 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -174,7 +174,7 @@ namespace
 
         if (!pv_node && !in_check && depth >= 4 && !at_root && do_null && position.should_do_null())
         {
-            int R = std::max(4, 3 + depth / 5);
+            int R = std::max(4, 3 + depth / 3);
 
             position.apply_null_move(search.stats.ply);
             int score = -pvs(search, depth - R, -beta, -beta + 1, false).score;
diff --git a/src/uci.cpp b/src/uci.cpp
index e2e5e22..7e55c14 100644
--- a/src/uci.cpp
+++ b/src/uci.cpp
@@ -27,7 +27,7 @@
 #include "polyglot.h"
 #include <cstring>
 
-const char *version = "7.38";
+const char *version = "7.39";
 
 namespace
 {