Former Premier League referee Keith Hackett has questioned how Newcastle United's goal was allowed to stand against Birmingham during their 3-2 FA Cup win. Joe Willock equalised after 22 minutes after the assistant referee adjudged that his close-range effort crossed the line, despite Bailey Peacock-Farrell's best efforts to keep the ball out.

Unlike VAR, which will be enforced in the next round, goal-line technology is in use for the fourth round fixtures at Premier League and Championship grounds.

Hackett told Football Insider: "I find it difficult to understand why after personally convincing the Premier League, and after years to convince FIFA to introduce Goal Line Technology it is not in operation in the Birmingham City v Newcastle United game.

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"The Hawkeye GLT takes away the guessing by match officials with regard to the ball crossing over the goal line. Newcastle United’s first goal was a guess and in a game at the top level this should not have to be the case.

"I was boss of the PGMOL when I asked the Premier League to introduce GLT, I worked with Dr Paul Hawkins of Hawkeye during its development.

"It took us years to convince FIFA of its introduction. It was only after Frank Lampard goal not given in WC that Blatter the Head of FIFA gave the go ahead."

Willock went on to round off the scoring as he netted the decisive goal late on to break Birmingham's resistance. Callum Wilson fired the Magpies in front but the lead was short-lived after Tomoki Iwata's wondergoal restored parity before eight minutes from time, the 25-year-old doubled his tally for the evening.