Following goals from Carlisle's Nathan Thomas and Walsall's Elijah Adebayo it looked like the spoils were going to be shared, however, Harry McKirdy's effort devastatingly deep into second-half stoppage time proved to be enough to see the visitors grab all three points.
Clarke admitted he was angry as his team failed to build upon recent results and insisted he will work on weeding out the so-called 'weak minded' players as his team failed to manage the game and slipped to a defeat.