Derbyshire have signed Western Australia batsman Marcus North as a replacement overseas player for Travis Birt during July. North will play much of the Twenty20 Cup while Tasmanian Birt is on duty with the Australia A side.
North has experience of English conditions after spending time with Durham and Lancashire.
The 26-year-old averages over 40 in first-class cricket and over 30 in the one day game and also bowls off-spin.
Birt, who 14 off three balls from spinner Muttiah Muralitharan during the recent tour match against Sri Lanka, hit his maiden first-class ton for Derbyshire against Leicestershire on Thursday.
Derbyshire had originally planned to bring Pakistan's Mohammad Yousuf in for part of the summer but suffered a mix-up over registration.
Yousuf will already be in England with his national team when Birt departs for the series against teams from New Zealand, India and Pakistan in Cairns and Darwin.