With James Posey out indefinitely with a right thumb injury, Heat coach Stan Van Gundy said Saturday he is leaning toward starting Antoine Walker at small forward in Wednesday's opener at Memphis.

Posey, who sprained his thumb Oct. 22 against Detroit, will wear a cast for another week before switching to a splint. Although he should be able to play with a splint, Posey said he has no timetable for a return.

''I'm not going to rush anything,'' he said after teammates practiced at AmericanAirlines Arena. ``I tried that last season [with different injuries], and it just set me back even worse.''

Walker, who usually plays power forward, was effective at small forward against Orlando on Thursday. ''Antoine in the lineup at the three worked very well for us, especially on the offensive end,'' Dwyane Wade said. ``And he did a good job defensively.''