diff --git a/package/AUTHORS b/package/AUTHORS
index e8e41573d9..4cd9d75a3a 100644
--- a/package/AUTHORS
+++ b/package/AUTHORS
@@ -280,6 +280,7 @@ Chronological list of authors
   - Amarendra Mohan
   - Shubham Mittal  
   - Charity Grey
+  - Dhanushka Weerakoon
 
 External code
 -------------
diff --git a/package/CHANGELOG b/package/CHANGELOG
index ca30fcb440..499baee788 100644
--- a/package/CHANGELOG
+++ b/package/CHANGELOG
@@ -17,11 +17,13 @@ The rules for this file:
 ??/??/?? IAlibay, orbeckst, marinegor, tylerjereddy, ljwoods2, marinegor,
          spyke7, talagayev, tanii1125, BradyAJohnston, hejamu, jeremyleung521,
          harshitgajjela-droid, kunjsinha, aygarwal, jauy123, Dreamstick9,
-         ollyfutur, Amarendra22, charity-g
+         ollyfutur, Amarendra22, charity-g, DhanushkaWeerakoon
 
  * 2.11.0
 
 Fixes
+ * Fix mismatch in target and reference groupselection coordinates which
+   can occur during RMSD calculations (Issue #2797) 
  * `MDAnalysis.analysis.atomicdistances.AtomicDistances` results are now
    consistent with expected `analysis` documentation data type = Results
    (Issue #4819, PR #5347)
diff --git a/package/MDAnalysis/analysis/rms.py b/package/MDAnalysis/analysis/rms.py
index 4b76723e7b..54dac2c0ff 100644
--- a/package/MDAnalysis/analysis/rms.py
+++ b/package/MDAnalysis/analysis/rms.py
@@ -733,7 +733,7 @@ def _prepare(self):
             if self._groupselections_atoms:
                 self._groupselections_ref_coords64 = [
                     (
-                        self.reference.select_atoms(
+                        self.reference.universe.select_atoms(
                             *s["reference"]
                         ).positions.astype(np.float64)
                     )