The boyband are in a public vote against Amy Mottram, Adam Burridge and Christopher Maloney to secure a spot in the finals.
Speaking about his Group wildcard pick, Walsh admitted defeat in the battle for Times Red on the programme.
"They look good, they sing well. They're a bit older. They're different," he said.
"But I know [who] I'm up against. I don't think they're going to get through."
Christopher Maloney is currently the bookies' favourite to land the wildcard, while Essex singer Mottram is the current pick from Digital Spy readers.
The X Factor Live Shows start on Saturday at 8pm on ITV1.
Watch Digital Spy's interview with X Factor wildcard Times Red: