diff --git a/NEWS.md b/NEWS.md
index eb259f0bc..ac65f5929 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,7 @@
+# Giotto 4.2.1
+## Bug fixes
+* fix `identifyTMAcores()` when no overlap relations are found and an `rbind` error is thrown
+
 # Giotto 4.2.0 (2024/01/17)
 
 ## Breaking Changes
diff --git a/R/spatial_clusters.R b/R/spatial_clusters.R
index 71f0bf292..f235533ba 100644
--- a/R/spatial_clusters.R
+++ b/R/spatial_clusters.R
@@ -231,6 +231,7 @@ identifyTMAcores <- function(
                 # determine sorted pairs of overlaps
                 apply(MARGIN = 2, sort) |>
                 t()
+            if (any(dim(ovlp) == 0)) ovlp <- NULL
             return(ovlp)
         })
         # combine test reps