We’ve all been there. It’s a nail-biting run chase, the required rate is climbing, and just as the batting side looks to launch… the heavens open. The covers come on, the crowd groans, and we all start the anxious wait.
For decades, this scenario was the death of a good cricket match. The old methods for calculating a new target were often laughably unfair (more on that later).
Then, two statisticians, Frank Duckworth and Tony Lewis, changed the game. Their system, now updated by Professor Steven Stern and known as the Duckworth-Lewis-Stern (DLS) Method, is the official way we get a fair result in a rain-shortened match.
But what is it, really? And how does it work?
Why Do We Even Need DLS? The “Bad Old Days”
First, you have to understand why the old “Average Run Rate” (ARR) method was so terrible.
Let’s say Team 1 scored 300 runs in 50 overs (an average of 6 runs per over).
Now, Team 2 starts their chase, but rain stops play, and their match is cut to just 25 overs.
Using the old ARR method, Team 2’s new target would be (6 runs x 25 overs) + 1 = 151 in 25 overs.
See the problem? Team 2 has to score 151 runs, but they still have all 10 wickets in hand. That’s incredibly easy for a professional side. This method completely ignored the value of wickets, making it a massive advantage for the team batting second.
The Big Idea: DLS Is About “Resources,” Not Just Overs
This is the most important part to remember. The DLS method is built on a simple, brilliant idea: Every team has two resources to score runs with.
- Overs to bat
- Wickets in hand
The DLS system understands that having 50 overs and 10 wickets is a team’s 100% resource.
But having 25 overs and 10 wickets isn’t 50% of your resource, because having all your wickets is a huge advantage. It’s maybe more like 65% of your resource.
Conversely, having 25 overs left but only 3 wickets in the shed is a tiny resource (maybe 25%). You can’t bat freely.
The DLS method is simply a giant, data-driven table that calculates a team’s scoring “resource” as a percentage, based on the combination of overs left and wickets lost.
How Does DLS Calculate a New Target?
So, when rain interrupts play, the umpires don’t just look at the run rate. They ask the DLS system to compare the resources of the two teams.
Let’s use a simple example.
Team 1 (Batting First):
- They bat their full 50 overs and score 280 runs.
- They used 100% of their available resources.
Team 2 (Chasing):
- They start their 50-over chase, but rain stops play.
- The umpires decide the match must be shortened to 40 overs total.
Here’s the DLS magic:
The system doesn’t just cut 10 overs off the target. Instead, it looks up the value of a 40-over innings. According to its data, a 40-over innings might only be worth 89% of the resources of a 50-over innings.
So, the DLS calculation adjusts Team 1’s score to match.
- DLS Calculation: Team 1’s Score (280) x Team 2’s Resource (89%) = 249.2
- The “par” (target) score for Team 2 is 249. To win, they need one more.
- New Target: Team 2 must score 250 runs in 40 overs.
This is much fairer. It recognizes that Team 2 has fewer overs to bat and adjusts Team 1’s total down to what it proportionally would have been in a 40-over match.
What is the “Par Score” on TV?
During a delay, you’ll often see a “DLS Par Score” on the screen.
This is the score the chasing team should have been on at that exact point (e.g., “After 20 overs, 2 wickets lost, Par Score is 92”).
- If Team 2 is 95/2, they are “3 runs ahead of DLS.”
- If Team 2 is 85/2, they are “7 runs behind DLS.”
If no more play is possible, the team that is “ahead of DLS” wins the match.
Common DLS Myths, Busted
Myth 1: “DLS always favors the team batting second.” Fact: It’s a neutral mathematical model based on scoring patterns from thousands of matches. It can feel tough for the team batting second because they have less time to plan their innings, but the calculation itself is balanced.
Myth 2: “It’s too complicated. Why did the target go up?” Fact: This can happen! Imagine Team 1 bats slowly (e.g., 25/0 in 10 overs) and the game is then cut to 20 overs. DLS knows that in a full-power 20-over T20-style game, a team should have scored much more than 25 runs. It adjusts the target to reflect what a “normal” 20-over score would be, which can sometimes be higher than the team’s slow start.
The Final Word
Is the Duckworth-Lewis-Stern method perfect? No. Cricket fans will always debate it, and it can feel a bit anti-climactic to win a match on a calculation.
But is it the fairest and most accurate system we’ve ever had? Absolutely.
It’s the best solution to cricket’s oldest and most annoying problem: the weather. So the next time you see that “DLS Target” flash on screen, you’ll know it’s not a random number – it’s a complex and fair calculation of cricket’s most valuable asset: resources.
