diff --git a/tests/instances.tcl b/tests/instances.tcl
index 26229804..6c71dcd5 100644
--- a/tests/instances.tcl
+++ b/tests/instances.tcl
@@ -79,7 +79,13 @@ proc spawn_instance {type base_port count {conf {}}} {
         close $cfg
 
         # Finally exec it and remember the pid for later cleanup.
-        set pid [exec_instance $type $cfgfile]
+        if {$type eq "redis"} {
+            set pid [exec ../../../src/redis-server $cfgfile &]             ;# WIN_PORT_FIX
+        } elseif {$type eq "sentinel"} {
+            set pid [exec ../../../src/redis-server $cfgfile --sentinel &]  ;# WIN_PORT_FIX
+        } else {
+            error "Unknown instance type."
+        }
         lappend ::pids $pid
 
         # Check availability
@@ -440,7 +446,11 @@ proc restart_instance {type id} {
 
     # Execute the instance with its old setup and append the new pid
     # file for cleanup.
-    set pid [exec_instance $type $cfgfile]
+    if {$type eq "redis"} {
+        set pid [exec ../../../src/redis-server $cfgfile &]               ;# WIN_PORT_FIX
+    } else {
+        set pid [exec ../../../src/redis-server $cfgfile --sentinel &]    ;# WIN_PORT_FIX
+    }
     set_instance_attrib $type $id pid $pid
     lappend ::pids $pid