Place chicken in a resealable plastic bag.  Add all remaining ingredients; seal bag and mix well.  Marinate in refrigerator for at least 2 hours.

Remove chicken and discard marinade, reserving orange slices if desired.  Grill over medium direct heat, 16 to 20 minutes, turning once until chicken is cooked through and center is at least 170°F.  Grill orange slices until nicely browned, if desired.

Remove from grill and let rest 5 minutes before serving.