The dire situation at right guard got worse Monday when Vikings coach Leslie Frazier announced that veteran Scott Kooistra was placed on injured reserve because of a serious and potentially career-threatening neck injury suffered in Saturday night's 20-7 win at Seattle.

Kooistra had begun taking reps with the first team along with Anthony Herrera, who is coming off ACL surgery in his left knee. Kooistra started Saturday night and would have stayed in the wide-open race to start at right guard. If Herrera can't start Saturday against the Cowboys, either Ryan Cook or Chris DeGeare will get the start. Frazier said "more than likely it will be Cook."

DeGeare was with the first team at right guard when camp opened. He lost his tentative grip on the position after the first preseason game and has been working as a backup right tackle since then.

Meanwhile, in a development that's potentially much more serious, the Vikings are sending All-Pro defensive tackle Kevin Williams to see a foot specialist this afternoon. They should have a better idea about the seriousness of the injury tomorrow.

Frazier said Williams' foot has been bothering him throughout training camp. He's had trouble pushing off. Letroy Guion ran with the first team at DT and has had an outstanding camp so far.

Meanwhile, in other practice news:

It was a light, non-padded practice that lasted about an hour and 10 minutes. TE Visanthe Shiancoe (hamstring) returned to practice for the first time in two weeks. WR Percy Harvin (ribs) also returned and even survived a pretty rough fall while making a catch. WR Greg Camarillo (groin), LB Kenny Onatolu (foot), LB Heath Farwell (hamstring) and DE D'Aundre Reed (hamstring) also returned.

Taking Kooistra's spot on the 90-man roster is Stylez G. White, the pass-rushing defensive end and former Gopher. His name was Greg White when he played for the Gophers.

Toby Gerhart was limited in practice because of ankle and Achilles' tendon soreness. LB Ross Homan suffered a concussion in Saturday night's game. LB Mark Washington injured his shoulder and also did not practice. CB Asher Allen (toe), FB Matt Asiata and CB Simeon Castille (hamstring) did not practice either.

QB Christian Ponder continued to work with the second team, but Frazier said he hasn't decided whether Ponder or Joe Webb will be with the second unit on Saturday against the Cowboys.