Cricket Evolution: The changes in field restrictions

November 28, 1979. England were facing the West Indies in the second ODI match of the Benson and Hedges series. The match went right down the wire and England's Ian Botham had to defend nine runs off the last over.

West Indies scored seven off the first five deliveries which meant they needed three off the final ball to win. England were already 1-0 down and desperately in need of a victory. That forced England skipper Mike Brearley to do something which completely changed the way how the game was played.

Brearley deployed all the fielders including the wicketkeeper on the boundary. Therefore, the batter on strike had to hit a four or a six or run three. There was no such rule at that time suggesting how many fielders can field at the boundary and how many must stay inside the circle.

The result of the match went in England's favour and that forced the administrators to think about making new rules for fielding.

Fielding restrictions were first used in the same tournament that took place in Australia in 1980-81. The rules were adopted for all ODIs after the 1992 World Cup. Since then, the rules have been modified multiple times to make the game more interesting and competitive. 

When the rules were first introduced, only two fielders were allowed outside the 30-yard circle during the first fifteen overs and the number was five for the remaining overs. 

Then came the concept of powerplay in 2005. The field restrictions were then divided into three blocks, each of them being called a powerplay. Ten overs at the beginning of the innings were known as the first powerplay and two fielders were allowed outside the circle, as usual. There were two more powerplay and each of them lasted for five overs. Only the bowling side had the authority to decide the time of powerplays.

So most often the teams chose to take those powerplays immediately so that they could put more pressure on the opponents by setting aggressive fields. 

The rule was modified in 2008 and the batting side was given the right to choose one of the two powerplays that were available after the first ten overs. 

The International Cricket Council (ICC) kept on making changes to the rules. According to the rule modified in October 2011, the number of powerplay would be three but they must not be taken earlier than the 16th over and be completed before the beginning of the 41st over. 

Further changes were made the next year as the number of powerplays was reduced to two. The most significant change was the number of fielders during the non-powerplay overs. From 1992 to 2012, it was five but in 2012 it was reduced to four.

According to this rule, the first powerplay was of course the mandatory one (first ten overs) with two fielders outside the circle. The second powerplay was to be completed before the 41st over and the number of fielders allowed in the outfield was three.

The rule was changed once more in 2015 and this time the second powerplay, known as the batting powerplay, was removed. Currently in ODIs, two fielders are allowed outside the circle for the first ten overs. Then during the period of over 11 to 40, four fielders can be stationed outside the circle. And to give the bowlers some lifeline at the death, as many as five fielders have been allowed in the outfield in the final ten overs.

In T20Is, the first six overs of an innings constitute the powerplay and the number of players in the outfield region is the same as for the ODIs. Teams can have a maximum of five fielders outside the circle from over 7 to 20.