Batsman Joe Burns is out and Daniel Vettori’s sore back will be assessed ahead of Brisbane Heat’s crucial domestic T20 clash against Sydney Thunder.

Batsman Joe Burns has been ruled out of Brisbane Heat’s must-win Twenty20 Big Bash League clash with Sydney Thunder on Wednesday but veteran New Zealander Dan Vettori could play at ANZ Stadium.

The defending BBL champions have won only one of their four matches so far this summer and need to beat fellow strugglers the Thunder to keep their slim semi-final hopes alive.

Burns has been unable to recover from a hamstring injury sustained in last weekend’s narrow loss to the Sydney Sixers and is expected to be out for at least the Heat’s next two matches.

The Heat have applied to get an exemption to bring another player into their squad as Burns undergoes treatment.

Left-arm spinner Vettori left the field with a sore back after hurting himself in the field during the loss to the Sixers but has responded well to treatment.

The 34-year-old will be assessed on Wednesday night before a final decision on his availability is made.

Australian trio Mitchell Johnson, Ryan Harris and Shane Watson remain unavailable.

Heat: James Hopes (capt), Dan Christian, Ben Cutting, Peter Forrest, Cameron Gannon, Nathan Hauritz, Craig Kieswetter, Chris Lynn, Alister McDermott, Luke Pomersbach, Chris Sabburg, Mark Steketee, Daniel Vettori (one to be omitted, 12th man to be named).