diff --git a/src/logging/writers/Ascii.cc b/src/logging/writers/Ascii.cc
index b926a6c55b..fc9567e9b7 100644
--- a/src/logging/writers/Ascii.cc
+++ b/src/logging/writers/Ascii.cc
@@ -175,6 +175,7 @@ bool Ascii::DoInit(const WriterInfo& info, int num_fields, const Field* const *
 			return false;
 			}
 
+		delete formatter;
 		formatter = new formatter::JSON(this, tf);
 		// Using JSON implicitly turns off the header meta fields.
 		include_meta = false;
@@ -186,6 +187,7 @@ bool Ascii::DoInit(const WriterInfo& info, int num_fields, const Field* const *
 		desc.EnableEscaping();
 		desc.AddEscapeSequence(separator);
 		formatter::Ascii::SeparatorInfo sep_info(separator, set_separator, unset_field, empty_field);
+		delete formatter;
 		formatter = new formatter::Ascii(this, sep_info);
 		}
 
diff --git a/testing/btest/core/leaks/ascii-log-rotation.bro b/testing/btest/core/leaks/ascii-log-rotation.bro
new file mode 100644
index 0000000000..a84f80ea90
--- /dev/null
+++ b/testing/btest/core/leaks/ascii-log-rotation.bro
@@ -0,0 +1,75 @@
+# Needs perftools support.
+#
+# @TEST-SERIALIZE: comm
+# @TEST-GROUP: leaks
+#
+# @TEST-REQUIRES: bro  --help 2>&1 | grep -q mem-leaks
+#
+# @TEST-EXEC: btest-bg-run receiver HEAP_CHECK_DUMP_DIRECTORY=. HEAPCHECK=local bro -b -m ../receiver.bro
+# @TEST-EXEC: sleep 1
+# @TEST-EXEC: btest-bg-run sender HEAP_CHECK_DUMP_DIRECTORY=. HEAPCHECK=local bro -b -m ../sender.bro
+# @TEST-EXEC: sleep 1
+# @TEST-EXEC: btest-bg-wait 60
+
+@TEST-START-FILE sender.bro
+
+@load base/frameworks/communication
+@load base/protocols/dns
+
+redef Communication::nodes += {
+    ["foo"] = [$host = 127.0.0.1, $connect=T]
+};
+
+global write_count: count = 0;
+
+event do_write()
+	{
+	print "do_write";
+	local cid: conn_id = conn_id($orig_h=1.2.3.4,$orig_p=1/tcp,
+	                             $resp_h=5.6.7.8,$resp_p=2/tcp);
+	local dns_info_dummy = DNS::Info($ts=network_time(), $uid="FAKE",
+	                                 $id=cid, $proto=tcp);
+	Log::write(DNS::LOG, dns_info_dummy);
+	schedule .1sec { do_write() };
+	++write_count;
+
+	if ( write_count == 200 )
+		terminate();
+	}
+
+event remote_connection_handshake_done(p: event_peer)
+	{
+	print "remote_connection_handshake_done", p;
+	schedule .1sec { do_write() };
+	}
+
+event remote_connection_closed(p: event_peer)
+	{
+	print "remote_connection_closed", p;
+	}
+
+@TEST-END-FILE
+
+@TEST-START-FILE receiver.bro
+
+@load frameworks/communication/listen
+@load base/protocols/dns
+
+redef Communication::nodes += {
+	["foo"] = [$host = 127.0.0.1, $connect=F, $request_logs=T]
+};
+
+redef Log::default_rotation_interval = 2sec;
+
+event remote_connection_handshake_done(p: event_peer)
+	{
+	print "remote_connection_handshake_done", p;
+	}
+
+event remote_connection_closed(p: event_peer)
+	{
+	print "remote_connection_closed", p;
+	terminate();
+	}
+
+@TEST-END-FILE