LOS ANGELES ? George Clooney and Penelope Cruz topped the list of Hollywood celebrities nominated Thursday for the 16th annual Screen Actors Guild (SAG) awards, unique as the honors in which actors toast their own.

Nominees for best male actor in a leading movie role included Morgan Freeman for "Invictus," Clint Eastwood's drama about former South African President Nelson Mandela's efforts to unite the apartheid-scarred country around the 1995 Rugby World Cup.

Also nominated were Jeff Bridges for "Crazy Heart," Colin Firth for "A Single Man," Jeremy Renner for "The Hurt Locker," and Clooney for "Up In the Air," the acclaimed story of a corporate downsizer who starts to question his role in life.

A best female acting nod went to Sandra Bullock in "The Blind Side," a drama about a white couple who give an illiterate black teen a home and a new lease on life.

Helen Mirren also received a nomination for "The Last Station," as did Carey Mulligan for "An Education," Gabourey Sidibe for "Precious," and Meryl Streep for "Julie and Julia."

The SAG awards are often viewed as a key barometer of which films may go on to challenge for honors at the Oscars, which will take place at Hollywood's Kodak Theater on March 7.

Ballots for the SAG awards were to be mailed on December 29 to some 100,000 actors and must be turned in by January 21, 2010 ahead of the January 23 ceremony.

In other key categories, nominees for supporting actor were Matt Damon, Woody Harrelson, Christopher Plummer, Stanley Tucci and Christoph Waltz.

The women in that category were Penelope Cruz for her work in the star-studded "Nine," about an Italian film director struggling to balance the demands of his tangled love life.

Also getting supporting female actor nods were Vera Farmiga, Anna Kendrick, Diane Kruger, and Mo'Nique for her role as an abusive mother in the gritty "Precious," about the struggles of an obese and illiterate teenager.

The SAG awards also nominate the year's best television performances, and the best work by the industry's stunt actors, as well as the best ensemble performance, this year singling out the casts of "Nine," "An Education" and Iraq war drama "The Hurt Locker," director Kathryn Bigelow's gripping story about a maverick bomb disposal expert.

Also nominated in the ensemble category were "Inglourious Basterds," Quentin Tarantino's blood-soaked World War II revenge fantasy, and "Precious."