Another Manchester City player Claudio Bravo suffered a ruptured Achilles tendon in training on Monday to become the second Premier League Champions stars to injured after Kevin de Bruyne.
The 35-year-old Chile international had scans in Manchester to confirm the injury and he will fly to Barcelona for further tests on Thursday.
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The news is a second injury blow for City in the space of a week after Kevin De Bruyne was ruled out for three months with knee ligament damage.
Bravo's injury leaves Pep Guardiola to name academy prospect Daniel Grimshaw among his substitutes at Molineux is yet to make a single senior appearance as Cityzen
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His presence allowed Spanish coach to sell England Under-21 goalkeeper Angus Gunn to Southampton in July and Joe Hart to Burnley in August.
Bravo has not featured in the Premier League this season but was part of the side that beat Chelsea 2-0 in the Community Shield.