diff --git a/src/compute_msd_chunk.cpp b/src/compute_msd_chunk.cpp
index 3b2730001a..317b601bc3 100644
--- a/src/compute_msd_chunk.cpp
+++ b/src/compute_msd_chunk.cpp
@@ -118,7 +118,6 @@ void ComputeMSDChunk::compute_array()
 
   if (firstflag) {
     nchunk = n;
-    size_array_rows = nchunk;
     allocate();
     size_array_rows = nchunk;
   } else if (n != nchunk)