Because of the Pillbox Hats, Lace-front Jerseys, Emboidered Cuffs and Quilted Pants, I would say pre-1900. I would guess early - mid 1890s, based on the Equipment, style of pose, ornate backdrop and overall appearance. Look at the length of the crotch area (ok, not too closely) and how low it goes... almost to the knees on the shorter guy!
Terrific piece with tremendous clarity for a photo of that vintage. Normally these are faded, out of focus, and/or washed out. This one was obviously well cared for.
