Miranda Lambert performs at the 50th annual Academy of Country Music Awards at AT&T Stadium on Sunday, April 19, 2015, in Arlington, Texas.ARLINGTON, Texas - Miranda Lambert and Florida Georgia Line are both double winners at the Academy of Country Music Awards.
Lambert won both as a songwriter and performer for song of the year for her hit "Automatic" on Sunday, while FGL won vocal duo of the year and vocal event of the year, shared with Luke Bryan for "This Is How We Roll."
"Oh hello, Texas!" Lambert yelled onstage. "It's good to be home tonight."
Lambert, a fashion favorite in the last year, wowed again in a flowing, plunging dress on the red carpet. Inside the venue, she wore white pants and a white top with a black sheer center. When she performed "Mama's Broken Heart" and "Little Red Wagon," she rocked a black and red bustier and disheveled hair.
She also accepted the 50th Anniversary Milestone Award, given to her by Reese Witherspoon and Sofia Vergara (Lambert wrote a song for their new film, "Hot Pursuit.")
"I'm nervous. I don't have any idea why I'm up here receiving this award with all these amazing artists," said Lambert.
Other recipients of the anniversary honor include Garth Brooks, Taylor Swift, Reba McEntire, Brooks & Dunn, Kenny Chesney and George Strait, who performed near the beginning of the show.
George Strait accepts the milestone award at the 50th annual Academy of Country Music Awards at AT&T Stadium on Sunday, April 19, 2015, in Arlington, Texas. The ACMs kicked off Sunday night paying tribute to veteran Merle Haggard, while Strait sang "All My Ex's Live in Texas" - appropriate for the awards show celebrating its 50th anniversary in a new location, the AT&T Stadium in Arlington, Texas.
Hosts Blake Shelton and Bryan introduced Strait as the "king of country music." Keith Urban and Eric Church both played guitar while Church sang "Pledge Allegiance to the Hag" in tribute to Haggard. Then - across at the second stage at the Dallas Cowboys Stadium - the country stars performed "Raise 'Em Up" as the audience danced along, including McEntire.
"How about it Texasssssss! Dallas!" Bryan said standing next to Shelton. "They say everything is bigger in Texas and that's why we came here."
Shelton announced that the 2015 ACM Awards - usually held in Las Vegas - set a Guinness World Record for most attended live awards show of all-time.
Florida Georgia Line were among the two-dozen performers: The duo sang the groove "Sippin' on Fire" surrounded by a ring of fire onstage.
Lee Brice sang some of "Forever and Ever, Amen" and then called out Randy Travis, who was sitting in the audience and earned a rousing applause. Swift, who brought her father to the awards show, got out of her seat to proudly sing along to "Independence Day" when Martina McBride performed.
Dierks Bentley, who performed, won video of the year for "Drunk on a Plane," while Little Big Town won vocal group of the year.
Shelton and Bryan were playful as hosts - and they even played some football. Shelton asked Dallas Cowboys quarterback Tony Romo to throw the ball to Bryan, who was wearing gloves.
"This isn't one of those deflated balls?" Shelton said after Bryan caught the ball, referencing the deflategate scandal earlier this year.
Shelton may be the show's host, a performer and two-time nominee, but he has another priority Sunday: being a cheerleader.
Shelton's wife, fiery country star Lambert, is the top contender with eight nominations, including the coveted entertainer of the year - an award she has yet to win.
"It needs to happen. It's imperative that it happens. Girls having the tough time that they're having right now at radio, it's not good for any of us. Especially somebody like Miranda - I think she deserves entertainer of the year," he said in an interview Friday.
"Not only will that be important for the industry, it's just freakin' right. It's just the right call," he added.
Lambert won the Grammy for best country album in February and she cleaned house at the Country Music Association Awards in November, winning four awards.
"I'm just thankful because I couldn't have dreamed this in a million years," Lambert said in an interview. "You dream of singing music that moves people and you hope that they love it, and then you get to a place like this."
Lambert is the sole female nominated for entertainer of the year - a trend repeated in other categories. Co-host Bryan, Brooks, Jason Aldean and Florida Georgia Line are also up for the fan-voted entertainer of the year.
Lambert, still, is expected to go home with a few wins: She will likely take home her sixth consecutive win for female vocalist of the year.
Swift, who also sang along while Lambert performed, won't be the only pop star in the building: Christina Aguilera will perform with Rascal Flatts, Nick Jonas will join Dan + Shay onstage and Kelly Clarkson will present an award.
The awards show, held in Las Vegas for over a decade, has transformed the Dallas Cowboys' six-year-old stadium to mark its anniversary. The show will feature 23 performances across two stages, and presenters include Troy Aikman, Tony Romo, Reese Witherspoon, Sofia Vergara and Steven Tyler, who is recording a country album.
Other performers include Brooks, Aldean, McEntire, Lady Antebellum, Alan Jackson, Brad Paisley, Brooks & Dunn and Little Big Town. The show is airing live on CBS.
Brian Kelley, left, and Tyler Hubbard, of Florida Georgia Line, perform at the 50th annual Academy of Country Music Awards at AT&T Stadium on Sunday, April 19, 2015, in Arlington, Texas.