Goodman claimed that he loves watching Riley performing, but argued that from a judge's perspective he can't ignore some of her technical faults.
"My brain looks at her dancing and thinks, 'Her posture is not good, she's cumbersome', but my heart is saying she's so much fun and got so much feeling going on. It's a challenge between my heart and brain," he told It Takes Two.
"My heart wants her to go through, but as a judge I have to judge with my brain and the viewers can judge with their heart. And well done to her!"
Riley is in this weekend's semi-final with Denise Van Outen, Kimberley Walsh, Dani Harmer and Louis Smith. So far, the Emmerdale actress hasn't been in the bottom two dance-off.
Watch Lisa Riley's cha cha cha:
Picking out his favourite contestant of the series so far, Goodman selected Girls Aloud star Walsh as his highlight.
Strictly airs on Saturday, December 15 at 6.30pm and Sunday, December 16 at 7.30pm on BBC One.