The band, which consists of Rochelle Humes, Una Healy, Vanessa White, Mollie King and Frankie Sandford, kept looking at Lopez when they saw her at the Golden Globe awards last month, reports thesun.co.uk.
"It was surreal. We saw her coming out of the lift. I missed her face, but saw her bottom," Mollie said. "I asked Una, 'What was her face like? How much make-up was she wearing?' Una said, 'I don't know, I just couldn't stop staring at the bottom'," she added.
The band members went speechless after seeing the diva. "We were like dudes checking her out. We were rabbiting away then she came out of the lift and we all went silent. I've never heard us so quiet," Mollie said.
"As she walked away you were completely drawn to her bottom," Una said. The band recently made its TV debut with reality show "Chasing The Saturdays".