Sri Lankan umpire Asoka de Silva was the most notable omission from the list of match officials for the quarterfinals. This isn't surprising.
The 54-year-old former leg-spinner has made several errors during the World Cup, notably giving Ireland's Gary Wilson out LBW when the ball had struck him outside the line of the stumps.
What's surprising is that the same yardstick hasn’t been applied to Daryl Harper, who has been retained despite being successfully challenged seven times, two more than de Silva.
In the Canada-Pakistan match, Harper was overruled four times in one innings. Is the Decision Review System making umpires less alert?
Also left out was Amish Saheba, who, it can be said, fared much better than Harper, till he blew it in the New Zealand-Sri Lanka match where he controversially ruled Mahela Jayawardene not out.
While Simon Taufel is low down on this list, he's been challenged only four times — which says much about his umpiring skills.
Here's the skinny on how umpires have coped with the challenges of the UDRS.
And which teams have made the best use of the DRS?
South Africa, Canada and Zimbabwe have made the most successful challenges. Pakistan, not surprisingly, have made the most overall challenges and West Indies the least.