diff --git a/src/tests/modules/punkcheck/testsuites/punkcheck/concurrency.test b/src/tests/modules/punkcheck/testsuites/punkcheck/concurrency.test
index 068dd433..bb207c96 100644
--- a/src/tests/modules/punkcheck/testsuites/punkcheck/concurrency.test
+++ b/src/tests/modules/punkcheck/testsuites/punkcheck/concurrency.test
@@ -68,6 +68,18 @@ namespace eval ::testspace {
             after 25
         }
     }
+    #cleanup for workspaces where background children were spawned with redirected logs: the
+    #done-marker appears before the child fully exits, so on Windows its log file can still be
+    #open (undeletable) for a beat - retry the tree delete briefly instead of flaking
+    proc cleanup_workspace {root} {
+        set deadline [expr {[clock milliseconds] + 10000}]
+        while {[catch {file delete -force $root} errdel]} {
+            if {[clock milliseconds] >= $deadline} {
+                error "cleanup_workspace '$root': $errdel"
+            }
+            after 100
+        }
+    }
 
     #added 2026-07-21 (agent, G-095) - concurrency suite: atomic saves, advisory event lock, stale-break, non-interactive recovery
 
@@ -157,7 +169,7 @@ namespace eval ::testspace {
             list parse_errors [llength $parse_errors] reader_ran [expr {$observed_loads > 0}] installer_problems $dup_or_missing missing_targets $missing_targets leftovers $leftovers
         }\
         -cleanup {
-            file delete -force [dict get $ws root]
+            cleanup_workspace [dict get $ws root]
         }\
         -result {parse_errors 0 reader_ran 1 installer_problems {} missing_targets {} leftovers {}}
 
@@ -194,7 +206,7 @@ namespace eval ::testspace {
             list errcaught $errcaught code_ok $code_ok names_holder [string match "*held by:*HOLDER-CHILD*" $errmsg] lock_cleared [expr {![file exists $pf.lock]}]
         }\
         -cleanup {
-            file delete -force [dict get $ws root]
+            cleanup_workspace [dict get $ws root]
         }\
         -result {errcaught 1 code_ok 1 names_holder 1 lock_cleared 1}