Retired referee Mark Halsey believes that his former colleague Howard Webb has lost his focus after failing to award a penalty during yesterday's FA Cup clash between Arsenal and Liverpool.

Around five minutes after Liverpool captain Steven Gerrard converted from the penalty spot, Luis Suarez was brought down in the box following a challenge from Alex Oxlade-Chamberlain.

Webb has suffered criticism for failing to award the spot kick after Arsenal managed to hold on for a 2-1 victory at the Emirates.

Former match official Halsey believes that Webb's off-field commitments have distracted his focus on the pitch.

"Howard has made an error of judgement," Halsey told talkSPORT. "He has not had the best of seasons. He has not been the Howard Webb we all know. Perhaps he may need a little rest because he is perhaps doing too much.

"He is not just refeereeing football matches, he is doing a lot of work outside of football. He is doing a lot of after-dinner speaking. Everyone wants Howard Webb because he was the World Cup [final] referee [in 2010].

"He has to take a good look at himself in the mirror and ask himself what he wants. This [refereeing] is his full-time job and he has got to concentrate on this."

Webb will be England's representative in this summer's World Cup in Brazil.