US media reports say a fever was to blame for Day's withdrawal but his absence from the course shouldn't come with huge concern.
At this year's Farmers Insurance Open, the former World No. 1 pulled out of the pro-am with back problems and won the tournament a few days later and did the same thing at the 2015 Barclays event.
Day lives in Ohio and is a member at Muirfield Village but he's yet to record a top 10 from nine starts over the Jack Nicklaus and Desmond Muirhead designed layout.
His form in 2018 has been outstanding however with two wins and a 5th place finish at his last start at the Players Championship.
This week's event takes on even greater significance with the US Open now just two weeks away and a host of other Australians are seeking either a final tune-up or late call-up for Shinnecock Hills.
Adam Scott is the only Australian in the field at Muirfield Village who can move into the US Open field with a great week.
Scott is currently 65th in the world rankings and needs to move inside the top 60 by June 11 to ensure his place in the second men's major of 2018.
If a strong performance at Jack Nicklaus' place this week eludes him, Scott will get another chance at next week’s FedEx St Jude Classic to earn an 11th hour US Open berth.
The former World No. 1 has missed only one cut in nine starts in the event, has several top tens and has produced some very low rounds at Muirfield Village including a round of 62 in 2007.
Scott has shown genuine signs of improvement in recent weeks and even in Fort Worth last week he recovered from a slow start with a final round of 64 to finish midfield.
Marc Leishman has played the Muirfield Village layout well in the last three years. Neither he nor Jason Day have the pressure of trying to get into the US Open and there is a lot to like about Leishman’s chances off the back of a runner-up finish in Dallas two weeks ago.
Given that Cameron Smith also has a start at the US Open, he has little pressure in that regard but will be keen to head to New York in good form.
He has not played this event well in his two starts at Muirfield Village with two missed cuts and will be keen to rekindle the form the showed in the opening major of the year when 5th at the Masters.
Rod Pampling finished 3rd at the Memorial earlier in his career but in more recent times there has been little to get excited about. His most recent starts do not suggest things will get a lot better this week.
Cameron Davis comes off the back of his great win on the Web.Com Tour last week and gets his first start in the event. The reigning Australian Open Champion and the World Amateur Champion appears on his way to greater heights than those he has already achieved and his play this week will be of much interest.
Like Davis, John Senden has a start courtesy of a sponsor's invite and although he has missed only one cut in nine previous starts in this particular event he is still slowly building his way back into tournament golf at present.
SWING LIKE JUSTIN ROSE
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