Liverpool were dumped out of the FA Cup by West Brom in a match littered with Video Assistant Referee referrals which caused confusion on the pitch and in the stands.
Three major incidents in the first half of the Reds’ 3-2 defeat required the intervention of technology — including the first time a match referee has used a pitchside television replay.
And although it eventually led to the correct decisions being made, the time it took — with almost four minutes elapsing between Mohamed Salah being fouled and Craig Pawson awarding a penalty which Roberto Firmino missed — left supporters and players on all sides angry and frustrated.
It detracted from an impressive performance by the Baggies, who became the first team since Real Madrid in October 2014 to score three in the first half at Anfield.
Jay Rodriguez scored twice in the first 11 minutes, following Firmino’s opener, with Joel Matip’s own goal giving the visitors a two-goal cushion.
Salah’s first FA Cup goal, and his 25th of the season, set up a thrilling finale but the Baggies held on to reach the fifth round for the third time in the last four seasons.
Firmino’s clever sixth-minute chip from Salah’s rebounded shot after a misunderstanding between goalkeeper Ben Foster and Jonny Evans was cancelled out just 71 seconds later when Rodriguez fired into into the top corner after Georginio Wijnaldum lost possession in midfield.
Rodriguez converted again, this time from six yards, after Chris Brunt sliced through Liverpool’s midfield.
The manic start was compounded when Craig Dawson headed in Brunt’s 20th-minute corner, only for VAR to spot Gareth Barry in an offside position in front of goalkeeper Simon Mignolet.
Three minutes later Salah was pulled back by Jake Livermore and — having not been satisfied with the information he received in his earpiece — Pawson made his way to the tunnel to view the television screen.