The NFL Scouting Combine participant list has been announced, allowing us to examine some under-the-radar storylines to follow during the event. Position changes Four players are listed on the combine invitation list at positions other than what they played in college -- and Northern Illinois quarterback Jordan Lynch isn't one of them. Conventional wisdom is that Lynch can't play quarterback at the next level and instead will have to be a running back or wide receiver. The four are Northwestern's Kain Colter (a quarterback listed at wide receiver), Utah's A.D. Denham (wide receiver to tight end), Georgia Southern's Jerick McKinnon (quarterback to running back) and UCLA's Xavier Su'a-Filo (tackle to guard). Su'a-Filo (6-foot-3, 305 pounds) is expected to be one of the first guards drafted; he started at both guard and tackle during his career with the Bruins. The others are considered third-day picks at best. Colter (6-0, 200) spent most of 2011 as a receiver and is a good athlete with good quickness, but he doesn't have an NFL arm. He missed two full games this season after suffering a concussion, and he had to withdraw from the Reese's Senior Bowl because of an ankle injury. Denham (6-4, 222) has a courageous back story -- he spent his high school days in the L.A. area in foster care -- and was a solid possession receiver in his two seasons with the Utes after transferring from a junior college. McKinnon (5-9, 215) missed some time this season with injuries but still rushed for 1,050 yards and 12 TDs in the Eagles' triple-option attack. He rushed for 125 yards in Georgia Southern's upset of Florida.