Wimbledon organizers have apologized and explained that “human error” was the reason behind the electronic line-calling system being turned off during a match on Sunday.

CENTRE COURT, THE ALL ENGLAND CLUB — Anastasia Pavlyuchenkova suggested her British opponent may have received preferential treatment as simmering tensions around Wimbledon ’s use of electronic line calling (ELC) instead of line judges boiled over Sunday, when the technology malfunctioned at a crucial point on Centre Court.

A ball that clearly landed long in a match at Centre Court wasn't called out Sunday because the electronic system that replaced line judges at Wimbledon this year accidentally was shut off for three points.