Pussycat Doll singer Ashley was in the bottom two for a second week running last week, despite scoring top marks from the judges.
Ashley, who was once a judge on ITV's Dancing On Ice, has faced criticism for her past 'professional' dance experience.
But Tess says that Ashley has been left in tears by the reaction to her appearance on the show, and thinks fans should give her a break.
She told the Metro newspaper: "I actually feel sorry for Ashley because she was in tears on Sunday night, when she was in the bottom two
“She’s got dance experience in a pop band, but she hasn’t necessarily danced in ballroom before, it’s a different genre and I’m sure she’s never done the Viennese waltz in her career with the Pussycat Dolls.
“I think cut her a little slack, she’s an absolute sweetheart and doesn’t deserve that!”
Despite Tess' plea, Ashley is tipped to be in the dance off again this week.
Tipped to join her is Lauren Steadman, but her pro partner AJ Pritchard thinks viewers should give them a chance.
He told The Sun newspaper: “We might not be at the top of the leaderboard because of what Lauren’s experience is but I feel that we connect with the audience.
“And I hope we’re at the top of the leaderboard in the public’s eyes."
He added: "Just because you’re at the bottom of the leaderboard, it’s about the people at home that are supporting you! It’s trying to use the positives the show brings, life is too short. We have to look at that.
“Lauren is a world champion athlete! She’s not a dancer. But she’s worked so hard and she’s proved she’s worthy of a place in that final.”
Strictly Come Dancing's semi-final airs Saturday night from 6:35PM on BBC One.