Danish international Krøldrup, an unused substitute in last week's 2-1 defeat at Goodison Park, will undergo surgery on Tuesday for a niggling groin injury. As a result, the 26-year-old is expected to have to wait until the end of September to make his debut for the Premiership club following his summer move from Udinese Calcio.
Everton's scorer against Villarreal, Beattie, suffered heavy bruising to a toe joint during Saturday's 2-0 league loss at home to Manchester United FC. The 27-year-old faces "some weeks" on the sidelines according to club physio Baz Rathbone.
Should Everton fail to overturn their deficit at Villarreal next Wednesday, they will also be missing Krøldrup and Beattie for any UEFA Cup first-round first-leg match on 15 September.
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