Usman Khawaja is joining Glamorgan earlier than planned after fellow Australian Shaun Marsh was named in his country's squad for their Royal London One-Day International series against England.
Khawaja initially signed as Glamorgan's second overseas player in this year's T20 Blast competition, will now arrive in Wales later this week and will be available for the county's next three Specsavers County Championship fixtures, starting with this weekend's clash at Warwickshire.
Glamorgan chief executive and director of cricket Hugh Morris said: "We have been in negotiation with Cricket Australia and Usman ever since Shaun was called up to the Australian One-Day team and we are delighted he will be joining us early as cover."
Morris continued: "Usman is a very talented cricketer, who has a fantastic Test record. I'm sure he will do a great job coming in for Shaun and be a positive influence on our young squad."
Despite arriving early, Khawaja will miss Glamorgan's final T20 Blast group match after being selected in the Australia A squad playing in India from August 17.
The 31-year-old will be available for the county's opening 13 fixtures of the competition, starting with an away match at Hampshire on July 6 - but will miss the final game against Surrey.