What is DRS in cricket? – Explained in detail

DRS in cricket stands for decision review system. It is the use of digital technology to confirm the decision of the umpire or referee, either the decision is right or not. The technologies including, slow motion replays, ball tracking, microphones and infra red ball are used for drs in cricket.

Before the invention of drs, the decision from the umpire was considered as the final decision, even if it was clear or unclear. But then DRS was introduced in cricket, which is available for both teams for a limited use.

DRS was invented for on field officials (umpires on ground) to check the unclear decisions. This was introduced for umpires to make clear and accurate decisions.But in recent years drs was introduced to give players and each team a chance to review unclear decisions(player review).

We cover complete details of drs including, rules of drs, invention of drs, and the controversies in drs in this article.

History of DRS in Cricket

Decision review system played an important role in cricket to achieve fair and correct decisions. DRS has been used in cricket for three decades. In the beginning it was not so important, but now it is an important part of international as well as domestic cricket.

DRS was used in many of the biggest cricket moments in the 1992 world cup. But the accuracy was not 100% accurate. Since then many new technologies have been introduced in drs to make it 100 percent accurate.

Who invented DRS in Cricket?

The invention of drs does not belong to one person or a group of peoples. It was the evolution of new ideas from many peoples, hence officially drs was first used in test cricket in year 1992. 

Before the invention of drs in cricket, the television replays have been used in  cricket. But these replays were only for cricket fans, not for umpire decisions. Later that time someone proposed to use these replays for accurate umpire decisions.

When was DRS first used in Cricket?

DRS was first used in cricket in a test match between India and South Africa in 1992.  The on-ground umpire was not sure of the decision, so he asked the third umpire to check the tv replay for an accurate decision. Then the third umpire checks the replays and tv and announces the decision to the on-field umpire, whether the decision is true or not.

The drs was first used for stumps and run outs only. When the umpire was not 100% sure, the third umpire checked the slow motion replays for accurate decisions on run outs and stumps. Then with the evolutions of technology, the drs system improved.

In 2008 the LBW decisions were also included in drs. This was first used in a test match between Sri Lanka vs India. It was officially announced by the icc in 2009 in a test match between Pakistan and New Zealand. 

Before the official announcement the drs system was a controversial topic. In the Sri Lanka vs India match only India took the benefit of drs. So drs was universally announced by ICC. It was introduced for ODI in 2011 and for T20 in 2017.

Rules of DRS in Cricket

If you know what drs is, you have to understand when and how drs can be called. There are many rules and requirements required to request for the drs. All rules are discussed below.

When team request for DRS

The drs can be requested, only if the umpire gives the original decision. After the umpire’s decision the challenging team has the time of 15 seconds to request for the drs. 

If the fielding team wants to review the decision, their captain can request for drs. On the other hand if the batting team wants to challenge the decision, the batsman can call the review.

Symbol for the DRS

To call the drs, the symbol is “T” with the hand. The desired team has to make a t with their hand to request for drs. If the timer of 15 seconds over, then the on-ground umpire has the right to accept the request or reject it.

How DRS In Cricket work?

When the drs is requested by the team, the on-ground umpire asks the third umpire to check the action replay. The third umpire first checks the delivery, if it is legal or no ball. If the delivery is legal and fair, the third umpire proceeds to the other elements to check the drs.

Technologies used to check the DRS

Following technologies are used to the check drs:

  • Ball-tracking technology: Multiple cameras have been used in this technology to track the path of the ball. This technology checks the path of the ball from point of release to the bouncing point. Ball tracking technology is used to to predict, either 

the ball hit the batsman or any other objects.

  • Snickometer Technology: Snickometer is used to detect the sounds coming, when the ball hits the bat or pad. It is used to determine the contact between the ball or bat or pad of a batsman.
  • Ulta Edge technology: This is the improved technology of snickometer, it is using video or sound combination to check whether the ball has touched the bat.
  • Hotspot Technology: hotspot is the technology which uses thermal cameras to detect heat generated by friction.

How many DRS are allowed?

  • How many drs in the test?: In test cricket each team is allowed 2 unsuccessful reviews in an innings.
  • How many drs in ODI?: only one unsuccessful review is allowed for each team in an ODI innings. 
  • How many drs in T20?: Like One day international there is also only one review allowed for each team in a t20 innings.

Umpire call rule in DRS

There are errors in technologies, like the projected path is not the actual path of the ball. The technology has several projected paths, what we see on the screen is one of the possible paths of the ball. So the ICC announced the umpire call review. 

According to this rule, if there’s any doubt with the technology and the review is not clear, then the on-field umpire’s call will be the final decision.

How accurate is DRS?

According to technology experts the drs in cricket is 90% accurate. The 10% is in doubt. But this happens rarely in cricket, clear run outs, stumps and lbw. 

Can the umpire change his decision?

If the on-field umpire gives the signal of out, in case of run out, edge and LBW. But after the review, the third umpire reviewed the decision using technologies, and found the decision opposite to the on-ground umpire’s decision. Then the on-field umpire has to change his decision according to the review.

Biggest controversy because of Drs

In 2013, a test match was played between England and Australia. Shan watson bowled to joe root, and the ball went to keeper hands. The on-ground umpire made a decision, that it was edge and joe root was given out.

Batmen requested a review, while checking the ultra edge through ultra edge technology. It was unclear that, either the ball had touched the bat or not. Although the third umpire also made a decision and Root was given out.

SInce then this incident is always the hot debate topic, when someone is talking about cricket rules, or drs.

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To summarize this discussion, drs is an important part of cricket. It has many advantages, or disadvantages also. The accuracy and technology used in drs is improving day by day. So in future drs will be better than now.

Frequently Asked Questions

Who is the king of DRS?

MS Dhoni, a former Indian cricketer and captain is the king of drs. When Dhoni requested for a drs it never went wrong.

What is the full form of DRS?

Decision review system is the full form of drs.

Who can call for drs in cricket?

Team captain from the fielding side and the batsman from the batting side can call for drs.

Which technologies are used in DRS?

Ultra edge, snickometer, hotspot and ball tracking technologies are used in drs.

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