 A cordon of close @-@ in fielders would be <unk> behind the wicket and on the leg side to exploit batting errors elicited by this bowling line . In these circumstances , a batsman can either duck and risk being hit , or play the ball . Defensive shots rarely score runs and risk being caught in the cordon , while the pull and hook shots can result in a catch on the boundary , for which two men were usually set in " leg @-@ theory " bowling . Leg theory had been practised previously without resort to short @-@ pitched bowling , usually by slow or medium @-@ pace bowlers . This type of leg theory was aimed outside the line of leg stump ; the object being to test the batsman 's patience and force a rash stroke . It was occasionally an effective tactic , but was unattractive for spectators and never became widely used except by a handful of specialists such as Fred Root , the Worcestershire bowler and Warwick Armstrong , the former Australian captain . 
