The Dutch international defender has been without a club since the summer, when his contract at Aston Villa ran out, and may be drafted in by Roberto Martinez as the coach looks to bolster his defensive options.
Vlaar had been tipped with a move to Manchester United as a potential replacement for Jonny Evans—who moved to West Bromwich Albion—although ultimately a move failed to materialise, with Louis van Gaal preferring to draft in Daley Blind as a partner for Chris Smalling.
Similarly, Vlaar underwent knee surgery during the summer, meaning that there was always a chance potential suitors would wait until January before making a move.
Now recovered, the 30-year-old is on the market and—with some of his best years still ahead of him—would represent a coup and a potential replacement for John Stones, who is again being linked with a move to Chelsea.
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According to the Liverpool Echo, Everton would face competition from the likes of AC Milan and Inter Milan, while there is also interest from Germany and Turkey.
It remains to be seen whether United too will renew their mooted interested in ‘Concrete Ron’.