The covers come on at Eden Gardens with the chasing side 74/2 after 9.3 overs. The big screen flashes a DLS par score, the commentators say the batting side is "ahead", and half the ground has no idea what that means. Twenty minutes later the umpires call it off, and the result is decided by a number most people never saw coming.
The DLS method looks like a black box, but the core idea is simple and surprisingly fair. This guide explains where it came from, how resources work, how revised targets and par scores are produced, and what all of it means when you've got a position open on R9EXCH and the rain arrives.
Why cricket needed the DLS method
Before 1997, rain rules in limited-overs cricket were crude. The most common approach simply compared run rates, which ignored wickets entirely. A side could be 120/9 or 120/1 and be treated the same. That produced some absurd targets.
Two statisticians, Frank Duckworth and Tony Lewis, introduced a method in 1997 built on one insight: a batting side has two resources, overs and wickets, and losing either reduces its scoring potential. Steven Stern later updated the model to reflect how modern teams score, and it was renamed Duckworth-Lewis-Stern around 2014 to 2015. That's the DLS you see today in ODIs and T20s, and the one behind every rain-affected result shown on R9EXCH.
Resources: overs and wickets together
Overs remaining
More overs left means more chance to score. Obvious, but it's only half the picture.
Wickets in hand
Wickets matter just as much, because they control how aggressively a side can bat. Twenty overs with nine wickets in hand is worth far more than twenty overs with two.
DLS combines the two into a single percentage called resources remaining, looked up from published tables. Here's an illustrative comparison. These are not the official figures, just a way to see the shape.
| Situation | Overs left | Wickets in hand | Resources (illustrative) |
|---|---|---|---|
| Start of a 50-over chase | 50 | 10 | Full, 100% |
| Middle, going well | 25 | 8 | Well over half |
| Middle, collapsing | 25 | 3 | Well under half |
| Late, wickets intact | 10 | 9 | A modest share |
Notice the middle two rows. Same overs, very different resources. That single difference is why DLS is fairer than any run-rate method.
How is a DLS target calculated?
The basic logic: work out the resources each side had (or will have), then scale the target by the ratio. If the chasing side has fewer resources than the side batting first, the target comes down. In top-level games the scaling also uses a reference score, so the arithmetic in the official software is more involved than a straight ratio.
Here's a hypothetical. Team one bats its full 20 overs and makes 168. Rain arrives during the break and the chase is cut to 15 overs. Say the tables give the chasing side roughly four-fifths of the resources team one had. A rough revised target would then be around 135 to 136 from 15 overs. Treat that as approximate; the official figure comes from the DLS software on the day, and R9EXCH markets settle on that official number.
The DLS par score: what "ahead" really means
During a chase that could be interrupted, the scoreboard (and the R9EXCH match centre) often shows a par score. It's the score the chasing side would need at that exact moment, given the wickets they've lost, to be level if no more play were possible.
Why wickets move par so sharply
Every wicket reduces the side's remaining resources, so par jumps. A team can be ten runs ahead of par one ball and behind it the next after a dismissal. That's why the 74/2 chase from the intro could be comfortably ahead, and 74/4 at the same point might be behind.
DLS myths vs facts
- Myth: DLS always favours the chasing side. Fact: it's designed to be neutral. Some situations feel kinder to one side, but that's not the intent.
- Myth: it's just run rate with extra steps. Fact: wickets in hand make it a very different calculation.
- Myth: you can work out the exact target in your head. Fact: you can estimate it, but the official number comes from the software.
What DLS means for your bets
When rain threatens, markets on R9EXCH are often suspended and reopen with new prices once the situation is clear. A side ahead of par as the rain arrives will usually see its price shorten sharply, because if play doesn't resume, they win.
Picture this: you backed the chasing side with ₹1,200 at 2.20 before the start. Rain comes with them eight runs ahead of par and no further play is possible. They win on DLS, and your profit is ₹1,440 before any commission. Had a wicket fallen just before the covers came on, the picture could have reversed. Session and Normal markets have their own settlement rules for overs not completed, so always check those before betting when rain is forecast.
The short version
- DLS treats overs and wickets together as a side's resources.
- Revised targets scale the first-innings score by relative resources.
- The par score is where the chasing side needs to be if play stops now.
- Every wicket pushes par up, so "ahead" can disappear in one ball.
Frequently asked questions
Who invented the DLS method?
Frank Duckworth and Tony Lewis introduced the Duckworth-Lewis method in 1997. Professor Steven Stern later revised it to better reflect modern scoring, especially in high-scoring one-day and T20 cricket, and the method was renamed Duckworth-Lewis-Stern around 2014 to 2015. It's now the standard approach in international limited-overs cricket and most leading domestic and franchise tournaments.
Why does losing a wicket change the par score?
Because DLS counts wickets as a resource. When a side loses a wicket, its remaining potential to score drops, so it needs a higher score at that moment to be considered level. That's why par can jump by several runs after a single dismissal, even though no time has passed and no runs have been scored.
How do rain-affected matches settle on R9EXCH?
Match result markets generally settle on the official result, including a DLS result. Session and Normal markets follow their own rules for overs that weren't completed, and those rules are shown with each market. If rain is forecast, read them before you bet so you know exactly what happens if play is cut short.
Keep reading the game
DLS makes most sense once you're comfortable with overs notation and run rates, which How to Read a Cricket Scorecard: What the Numbers Really Say covers in detail. For how rain affects the different market types, see Match Odds vs Bookmaker vs Normal: Which Cricket Market When.
Want to see a revised target in action? Rainy season fixtures on the tournaments page are the place to watch for one.