Billy Slater insisted the Queensland Maroons would still have a "a great fullback" on the field to take on the NSW Blues as he revealed his disappointment at pulling out of Wednesday's State of Origin clash at the MCG.

The Maroons are flying Anthony Milford and Kalyn Ponga to Melbourne as cover and have the option of switching Michael Morgan to fullback and playing one of the duo on the bench, most likely Milford.

Milford landed just after 6pm in Melbourne on Monday night from Brisbane but did not speak to waiting media, with Ponga set to arrive later in the evening.

Slater was "extremely disappointed" at being forced to withdraw but said any option the selectors went with would still result in an accomplished custodian taking the field.

"We have a few options. I'm not too sure which way Kevvie and the selectors are going to go but whichever way we go we will have a great fullback and a good side," Slater said after landing at Melbourne airport.

"[Ponga's] been great this year. Whichever way we'll go we'll have 17 fit players out there for Queensland."

Michael Morgan is set to start at fullback in Wednesday's Origin for injured star Billy Slater. ©Scott Davis/NRL Photos

Slater, after speaking to coach Kevin Walters, told his teammates at lunchtime that he was out after consulting the team doctor and physio.

"I just didn't pull up as well as I wanted to after training yesterday," he said.

"I've never had a hamstring injury before so I don't have anything to measure it off so I went off the recommendation of the physio and doctor about what was best not only for myself, but the team as well.

"You don't want to miss out on any Origin but I've made the mistake of playing injured in the past and I regret that. I wanted to make the right decision this time."

Slater said he was not prepared to leave the Maroons in the lurch and with one man short in the Origin cauldron.

"I have played with pain before but that is not the issue," he said.

"It is about the repercussions of playing with this strain. If I pulled up tight and sore from a 40-minute training session, an 80-minute Origin, who knows what it is going to do?

"It is more about what could happen and the last thing I want to do is 20 minutes into the game come off and sit on the sideline and leave us with 16 men.

"It is a big occasion on Wednesday night and myself and Queensland aren't prepared to go in 80 or 90 per cent fit. The last thing I wanted was to be a distraction to the team so hopefully that is out of the road.

"My focus now it to get my hamstring right and get back on the field, whether that is for the Storm or Queensland hopefully that is not too far away."

Witness Australia's greatest sporting rivalry when Origin comes to the Melbourne Cricket Ground on Wednesday, June 6.

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