diff --git a/mesh_looptools.py b/mesh_looptools.py
index 4911f383f759061a9f24d27f5518bf87d3a8b224..06a1cc4dda05e2a7ebf520b77d086d05bd3abb20 100644
--- a/mesh_looptools.py
+++ b/mesh_looptools.py
@@ -2815,6 +2815,7 @@ def gstretch_match_loops_strokes(loops, strokes, object, bm_mod):
 
     # calculate loop centers
     loop_centers = []
+    bm_mod.verts.ensure_lookup_table() # to work in 2.73 
     for loop in loops:
         center = mathutils.Vector()
         for v_index in loop[0]: