Most Productive Overs method

The Average Run Rate method was replaced in 1991 by the Most Productive Overs method,[1] having been developed by Australia after the third 1989 Australian Tri-Series final between Australia and the West Indies.[2]

Chasing Australia's 226/4 off 38 overs, the West Indies needed 180 off 31.2 overs when rain had stopped play for one hour and 25 minutes. Under the average run-rate method, the revised target was 108, meaning the West Indies needed 61 off the 11.2 overs that remained. After the West Indies won the match (and the competition) by eight wickets with 4.4 overs remaining, Australian fans loudly booed this unsatisfactory conclusion, which was criticised by the media and Australia's captain Allan Border.[2]

If an interruption means that the innings of the team batting second is reduced to a total of X overs, their target score is adjusted as follows:

${\displaystyle {\text{Team 2's new target from their total of X overs }}={\text{ Runs scored by Team 1 in their highest-scoring X overs }}+1.}$

Whereas the Average Run Rate method heavily favours the team batting second (Team 2), the MPO method only favours the team batting first (Team 1). [3]

There are four intrinsic flaws in the method:

• Firstly, it effectively penalises Team 2 for good bowling by ignoring their best overs in setting the revised target.
• Secondly, the method takes no consideration of wickets lost, but how Team 1 scored their total.
• Thirdly, substantial bookwork is required by the umpires and officials to determine the revised target.
• Fourthly, if the least productive x overs were maiden overs, Team 2 would be left in the position of matching or beating Team 1's actual score but with fewer overs to do so.

Two subsequent modifications were used: resetting the target based on the x consecutive most productive overs of Team 1's innings (where x is the number of overs Team 2 is to face), and reducing the target by 0.5% for each over lost, the revised target being given by the next highest integer.

While these modifications reduced Team 1's advantage, they only addressed the fourth intrinsic flaw of the method.