diff --git a/phpseclib/Net/SFTP.php b/phpseclib/Net/SFTP.php
index 53833aba..04ad79c4 100644
--- a/phpseclib/Net/SFTP.php
+++ b/phpseclib/Net/SFTP.php
@@ -1878,7 +1878,7 @@ class SFTP extends SSH2
             $offset = $start;
         } elseif ($mode & self::RESUME) {
             // if NET_SFTP_OPEN_APPEND worked as it should _size() wouldn't need to be called
-            $size = $this->size($remote_file);
+            $size = $this->stat($remote_file)['size'];
             $offset = $size !== false ? $size : 0;
         } else {
             $offset = 0;