The ten-bout card, taking place at the Philips Arena in Atlanta, will be the UFC's first stop in the state of Georgia since UFC 13 in May 1997.
Canada's Day (17-6) won his UFC debut in April against Alan Belcher but was completely outmatched in his next fight in a TKO loss to Michael Bisping in June.
Lambert (23-8), who opened his UFC and WEC career winning six out of seven, has lost his last two fights this year. Lambert's biggest win was against Renato "Babalu" Sobral via TKO at UFC 68 "Uprising" in March 2007.
UFC 88: Breakthrough
Saturday, September 6, 2008
Philips Arena in Atlanta, Georgia
205 lbs. | Chuck Liddell vs. Rashad Evans
205 lbs. | Rich Franklin vs. Matt Hamill
170 lbs. | Karo Parisyan vs. Yoshiyuki Yoshida
185 lbs. | Dan Henderson vs. Rousimar Palhares
185 lbs. | Martin Kampann vs. Nate Marquardt
155 lbs. | Thiago Tavares vs. Kurt Pellegrino
205 lbs. | Tim Boetsch vs. James Lee
170 lbs. | Matt Brown vs. Dong Hyun Kim
170 lbs. | Roan Carneiro vs. Ryo Chonan
185 lbs. | Jason Lambert vs. Jason Day