Fielding is the most important part in the game of cricket. Legends of the game have always emphasised on this point that “ a good batsman may or may not score runs in every match, a good bowler may or may not take wickets in every match but a good fielder will always save runs.
A field is supposed to be set as per the choice of the bowler or the captain. Preferably the bowler has to make the call to set a particular field to which he is the most comfortable bowling too, as it is the bowler who is the best judge of what shot is the batsman going to play to which delivery.
There are four important factors that need to be taken into consideration before setting a field. The type of bowler, condition of the ball, the pitch and the type of match being played( Test, limited-overs or T20)
There can be different types of fields as per which type of bowler is bowling, what type of match is being played and the situation the match is in. In general, there are three types of fields, the first one is an attacking field, in this kind of field setting the majority of fielders are inside the 30-yard circle and close to the batsman. This field is usually used in test matches and in situations where the batsman needs less than 4 runs in one ball. The benefit of a field like this is more prominent in test matches where the focus for the batsman is not on hitting boundaries but surviving for a long period. It is spin bowlers who are seen using this field the most, as the chances for the batsman edging the ball are more and fielders close in always keep the batsman on the front foot.
The second type of field setting is a balanced field, in this field, there needs to be an equal number of fielders inside and outside the 30-yard circle. Usually used in limited-overs and T20 cricket. It is both fast bowlers and spinners who benefit from this kind of field. The motive of setting this kind of field is to restrict the outflow of runs and not to take wickets. Bowlers who are medium paced and tend to get the ball to swing are known to be the best with these field settings
The third kind of field is a defensive field setting, which actually used quite a lot in matches which are extremely tight. A field where maximum fielders are present at the boundary. The main achievement of setting a field like the is to get the wicket of the batsman. This field is also set to stop boundaries but wickets are the main motive to set this field. I would say every bowler has an upper hand with a field like this but it is the spinners who love to bowl to this kind of field as they trick the batsman to take them on and give their wicket away by getting caught in the deep.
As a spinner myself I love it when I get the ball to flight and the batsman thinks its a free hit while he ends up hitting the ball high but not long enough for it to cross the ropes!
To sum up, the question is not what field the bowler sets but the question is that does the bowler set the right field in the right circumstances!