Glamorgan will be without opener Gareth Rees for their Twenty 20 visit to bottom side Middlesex Panthers.
Batsman Rees has aggravated a hand injury so Glamorgan's leading run-scorer in all competitions will miss Tuesday's clash at Old Deer Park.
The Welsh county will also be without James Harris as the seam bowler is suffering with a foot problem.
Glamorgan's only t20 win this season was their opening day victory over Middlesex in Cardiff.
Glamorgan Dragons squad: Petersen (capt), Cosgrove, Allenby, Wright, Cooke, Wallace (wk), Wagg, Owen, Croft, Cosker, Jones, Brown, O'Shea