On Sunday, the Screen Actors Guild presents its annual awards. Usually, the winners of the SAG awards go on to win Academy Awards. With this year’s Oscar nominations thrown into chaos after presumed front-runner “Dreamgirls” was left out of a Best Picture nomination, the SAGs gain special importance. 

Helen Mirren, Forest Whitaker, Eddie Murphy and Jennifer Hudson were the presumed front runners heading into the Oscar nominations. But after “Dreamgirls” lost out in the Best Picture race when nominations were announced on Tuesday, Hudson and Murphy may be vulnerable.

Tvguide.com predicts that Alan Arkin’s portrayal of a cantankerous grandfather in “Little Miss Sunshine” will beat Murphy’s turn as a tragic r&b singer in “Dreamgirls” for Best Supporting Actor. 

Theenvelope.com polled some critics and bloggers. All agree that Mirren will win Best Actress for her portrayal of the title character in “The Queen.” Many look to Whitaker to take Best Actor for his portrayal of dictator Idi Amin in “The Last King of Scotland.”

But theenvelope.com columnist Tom O’Neil thinks sentimental favorite Peter O’Toole will win on Sunday for his portrayal of a lonely old actor in “Venus.” If O’Toole wins, look for him to take the Oscar, a prize he hasn’t won despite seven previous nominations.

Many feel that Hudson will take the prize for Best Supporting Actress for her touching performance as a feisty, overweight singer who’s kicked out of her group in “Dreamgirls.” If she loses this award, chances could be bleak for her Oscar.

With the exclusion of “Dreamgirls,” the Best Picture race is up in the air. Although SAG does not give up such an award, it does have a Best Ensemble prize. The experts at theenvelope.com did not agree on a winner in this category. But whatever film wins, it would then be seen as the front runner for the Academy Award  — unless, of course, it’s “Dreamgirls.”