The ICC has made a slight but significant alteration to the 2.5m rule, the most controversial segment of its decision review system (DRS) used in this World Cup, to enable more consistent application by the umpires. The change to the DRS rule No. 3.3 - which expands the umpire's scope for interpretation - follows its contrary usage in the first two weeks of the competition.

An ICC spokesperson confirmed to ESPNcricinfo that the umpires have "changed the protocol" in the clause to ensure a "consistency" of on-field umpires when using the DRS pertaining to not out lbw reviews.

A directive has gone out from the ICC's Umpires & Referees manager to all umpires that if an lbw appeal shows that even though there may be a distance between the stumps and the point of impact of 2.5m or greater, the on-field umpire can think of reversing the decision even if the replay shows that the ball is hitting "any part of the middle" stump.

The previous rule required that the leg-before could be reversed - by the on-field umpire - only if the replay showed that the ball was hitting the middle stump dead centre. This change in the 'protocol' was brought into play in the India v Ireland match in Bangalore, when umpire Rod Tucker reversed his lbw decision against Alex Cusack off the bowling of Yuvraj Singh. Tucker was heard on the stump microphone asking third umpire Marais Erasmus to let him know whether the ball was hitting "any part of the middle stump." The third umpire, it was confirmed, was also required to give the on-field umpire "all relevant information" during an lbw review and not merely specific pieces of information during the DRS process.

Teams had also been informed of this alteration in the rule and Yuvraj said later that while he "did not understand the 2.5 rule much", he knew it had been what he called "removed." He said the current rule stated that if, "the ball is hitting the line, it's out... I was just discussing it with Dhoni, so I took the referral."

The application of the same 2.5m rule had led to two contrasting reviews under the DRS last week, one involving Ian Bell - in England's match against India - and the other the Zimbabwe captain Elton Chigumbura against New Zealand. Both batsmen were struck well forward from the stumps but the not out decision against Bell's was not overturned while Chigumbura was declared out.

The 2.5m clause was included in the DRS rules following the expert view that the predictive path of the ball-tracker technology (in this case Hawk Eye) lost its accuracy when the distance between the point of impact and the stumps was greater than 2.5m.

Sharda Ugra is senior editor at ESPNcricinfo