Trae Patton/NBC(LOS ANGELES) -- Fans are asking America's Got Talent host Terry Crews to "stand up" for his now former co-worker Gabrielle Union, who was fired after reportedly expressing concerns over allegedly racially insensitive situations during her time as a judge.

After a full week of support from celebrity friends, including the likes of Viola Davis and Ellen Pompeo, Union tweeted a message of "gratitude" to those who had her back.

"So many tears, so much gratitude," Union wrote. "THANK YOU! Just when you feel lost, adrift, alone... you got me up off the ground. Humbled and thankful, forever."

In response to her tweet, Crews tweeted the reply, "You're the best, Gabrielle! You will be missed!"

Not surprisingly, fans were quick to question Crews on his seeming lack of support for Union, who in 2017  publicly supported him during his sexual assault revelation.

"Come on Terry, you know this ain't right," one fan wrote. "Gabby spoke out and potentially damaged some of her own professional relationship to support you when you wanted, desired support and all you can say is tantamount to 'sorry, sucks to be you?'"

"She had your back and yet you can't have hers," another fan shared.

One fan added that Crews should have done more.

"Stand up for your sister!!!," the fan tweeted. "I'm disappointed...you're one of my fave actors...don't let a paycheck keep you from what's right."

Variety reported that Union, along with Julianne Hough, won't return for AGT's upcoming 15th season. Union had reportedly complained to NBC about several problematic situations, and was also told that her frequently-changing hairstyle was said to be “too black” for AGT‘s audience.

Over the weekend, America's Got Talent's producers released a statement about the issue, declaring, "We remain committed to ensuring a respectful workplace for all employees and take very seriously any questions about workplace culture,” and said they're “working with Ms. Union through her representatives to hear more about her concerns, following which we will take whatever next steps may be appropriate.”

Additionally, SAG-AFTRA, the union for TV, film and voice performers, says they're investigating Union's claims.

Crews, Simon Cowell and Howie Mandel are all expected to return to AGT.

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