The 21st edition of the SAG Awards kicks off Sunday afternoon amid sunny weather, a vast array of starry presenters and nominees and a battle between “Birdman” and “Boyhood.”

The red carpet at the Shrine Auditorium will launch around 3 p.m. following toasting ceremonies with Champagne Taittinger, the official champagne of the SAG Awards for the past 15 years.

The SAG Awards website will live stream the red carpet.

The no-host ceremonies will launch at 5 p.m. PT with a live broadcast on TBS and TNT with the usual “I’m an actor” intro, followed by the presentation of five film and eight TV awards.

Presenters include Patricia Arquette, Ellar Coltrane, Kevin Costner, Ethan Hawke, SAG-AFTRA president Ken Howard, Rashida Jones, Michael Keaton, Lorelei Linklater, Matthew McConaughey, Edward Norton, Julia Roberts and Emma Stone.

Debbie Reynolds will be on hand to accept the SAG Life Achievement Award from daughter Carrie Fisher.

With the Oscars less than a month away, the SAG Awards are arriving on the heels of “Birdman” winning the Producers Guild of America’s Darryl F. Zanuck Award for best movie — elevating its status as an awards season frontrunner, since the last seven PGA winners have gone on to win the best picture Oscar. “Boyhood” had been the consensus favorite to win the PGA trophy.

The SAG Awards have provided strong signals as to who will take home the top prizes at the Academy Awards. The voting body is made up of 111,228 eligible SAG-AFTRA members, and actors represent about 20% of Oscar voters.

“Birdman” comes in with four nominations followed by “Boyhood,” “The Imitation Game” and “The Theory of Everything” with three each and “Foxcatcher” with a pair.

About 80% of SAG winners in the individual acting categories have gone on to win Oscars. The last four Oscar winners — Matthew McConaughey and Jared Leto for “Dallas Buyers Club,” Cate Blanchett for “Blue Jasmine” and Lupita Nyong’o for “12 Years a Slave” — had all won SAG trophies a few weeks earlier.

Winners of the SAG ensemble trophy are far less likely to win the best picture Oscar, matching only nine times in 19 years. The “American Hustle” cast won the SAG award last January and then was shut out at the Oscars.

J.K. Simmons is widely expected to repeat his Golden Globe win for actor in a supporting role for his performance in “Whiplash” and Patricia Arquette should continue her winning streak for her role as the complex mother of “Boyhood.”

Michael Keaton is viewed as likely winner for “Birdman” over a formidable field — Eddie Redmayne, “The Theory of Everything”; Benedict Cumberbatch, “The Imitation Game”; Steve Carell, “Foxcatcher”; and Jake Gyllenhaal, “Nightcrawler.”

Julianne Moore appears to be the frontrunner in the actress category for her heart-wrenching performance in “Still Alice” over Jennifer Aniston, “Cake”; Felicity Jones, “The Theory of Everything”; Rosamund Pike, “Gone Girl”; and Reese Witherspoon, “Wild.”

The ensemble award is the hardest category to predict between  “Birdman”; “Boyhood”; “The Grand Budapest Hotel”; “The Imitation Game”; and “The Theory of Everything.”

Even though it has only one nomination, “The Grand Budapest Hotel” could surprise, particularly since it won top prize for comedy/musical film at the Golden Globes. But the consensus is that “Birdman” — a film about actors — has the best shot.

The next SAG Awards has already been set for Jan. 31, 2016.