DLS Method Explained Simply: Cricket's Rain Rule for Fans
What the Duckworth-Lewis-Stern (DLS) method is, explained without mathematics — why cricket needs a rain rule, how DLS sets revised targets, why a team chasing 200 from 50 overs may only need 130 from 30 overs after rain, and when DLS controversies arise.
The Duckworth-Lewis-Stern (DLS) method is the mathematical system used to reset batting targets in rain-affected limited-overs cricket matches. When rain interrupts a match after the first innings is complete (or partially complete), DLS calculates a new target for the team batting second based on what is achievable with the remaining overs, using historical data about how many runs teams typically score from different starting positions. DLS replaced the earlier 'run rate' rain rule system after the 1992 World Cup semifinal controversy (South Africa famously needing 22 from 1 ball after a rain break).
Why DLS Isn't Simply Reducing the Target
A common misunderstanding: DLS doesn't simply calculate 'team needed 200 in 50 overs, so they need 120 in 30 overs (60% of target)'. This would be unfair because: (1) If the team batting second has lost wickets, their remaining resource is different from a fresh team's. (2) Run-scoring rates are NOT linear across an innings — teams score most aggressively in the powerplay and at the death (final 10 overs), and less aggressively in the middle. (3) A team chasing with all 10 wickets in hand in 30 overs has MORE resource than a team chasing in 30 overs of the original 50 — they can bat more aggressively.
Resources: The Key Concept
DLS calculates 'resources' — a percentage representing how much batting capacity a team has remaining, combining their overs remaining AND wickets remaining. A team at the start of their innings (50 overs, 10 wickets) has 100% resources. A team at 20 overs, 5 wickets has approximately 50% resources remaining — roughly. The specific percentages are derived from a large database of historical match data. DLS then calculates: what score would the first team have achieved if they'd had these resources? That is the revised target. The calculation is done by the match referee's software; the on-field scoreboard shows the revised target in real time.
The 1992 World Cup: Why DLS Was Needed
The 1992 Cricket World Cup semifinal between South Africa and England (at Sydney) is the most notorious rain-rule controversy in cricket history. South Africa needed 22 from 13 balls; rain interrupted play. The pre-DLS 'most-productive overs' rule was applied — the slowest over of England's innings was removed from the target calculation, and South Africa's target went from 22 from 13 balls to 22 from 1 ball. South Africa needed a boundary and six off one delivery — effectively impossible. They scored 1 run and lost. The absurdity of the outcome directly motivated Frank Duckworth and Tony Lewis to develop the DLS mathematical model, which was adopted by the ICC in 1997.
Frequently asked questions
What is the DLS method in cricket?
Duckworth-Lewis-Stern — the mathematical system for recalculating batting targets in rain-interrupted limited-overs cricket. It uses a 'resources' concept (combining overs remaining AND wickets in hand) to calculate a fair revised target rather than simply proportionally reducing the score. Adopted by ICC in 1997 after the 1992 World Cup 'most-productive overs' controversy.
Why does DLS sometimes give a lower target than expected?
Because a team chasing with all 10 wickets in hand in 20 overs has MORE batting resource per over than the first team had in their corresponding situation. DLS accounts for the fact that an aggressive team in 20 overs with full wickets can score at 10+ per over in the powerplay and death — more than a proportional share of their original 50-over target. The revised target reflects what that resource advantage is worth.
What was wrong with the pre-DLS rain rule?
The 'most-productive overs' rule used in the 1992 World Cup removed the least productive overs from the first team's innings when calculating a revised target — regardless of where they fell in the innings. Since dot-ball-heavy middle overs were often removed, this unfairly inflated targets. The South Africa 1992 semifinal (needing 22 from 1 ball after a rain reduction) is the most extreme example of the absurdity it could produce.