With one punch, Evans changed all that, landing an overhand right that instantly dropped Liddell. Referee Herb Dean rushed to stop the fight, and doctors immediately jumped in the ring to tend to Liddell.
Evans, unbeaten but unheralded coming into the fight, raised his record to 17-0-1. Liddell, losing for the third time in his last four fights, dropped to 21-6.
UFC's former light heavyweight champion and breakout celebrity star stalked Evans through the first round but couldn't land a clean shot. After a rare flurry of punches, Evans danced and smiled. But the former Michigan State wrestler did little to challenge Liddell other than a couple of ineffective leg kicks.
Evans countered and opened a small cut on Liddell's cheek in the second round, but Liddell continued to press the action. Evans seemed intent on luring Liddell into a defensive mistake. He got it, then capitalized with stunning brutality. The former champion dropped with a thud, then remained in a daze for several minutes.
"I was trying to get him to come out of his comfort zone because usually he likes you to chase him," Evans said.
UFC's first fight card in Atlanta drew a near-capacity crowd to Philips Arena that loudly cheered every time Liddell appeared on the big screens throughout the evening. When the lights went out for Liddell's entrance, hundreds of cell-phone cameras lit up the arena. Evans' introduction drew loud boos.
UFC president Dana White announced a crowd of 14,736 and a gate of $2.6 million, expressing disappointment only that the card didn't beat Barbra Streisand's arena record gate.
"We want a rematch with Barbra," White said in discussing future possibilities in Atlanta.
White also said Evans would be next in line for a shot at champion Forrest Griffin.
Liddell, 38, gamely attended the postfight press conference but wouldn't address his future.
"I've always said I'm going to retire in the training room, not after a fight," he said.
In the co-main event, former middleweight champion Rich Franklin moved up to light heavyweight to face Matt Hamill, who had trained with Franklin to help develop the veteran's wrestling skills. Hamill may have taught him too well, as Franklin stopped the up-and-coming fighter's takedown attempts and wore him down with effective kicks, putting him down and forcing a stoppage with a kick early in the third round.
Both fighters seemed wary in an uneventful start, but each had drawn blood by the end of the first round. Referee Mario Yamasaki stopped the action in the second round to have a doctor check the cut over Franklin's right eye, but action resumed with Franklin escaping after a Hamill takedown.
The action stopped again when Franklin landed a kick to Hamill's groin. Upon resuming, Franklin continued to kick Hamill at will. At the 0:39 mark of the third round, Franklin (26-3) landed his cleanest shot yet to Hamill's body. Hamill (6-2) crumpled and fell, and Yamasaki waved the fight to a close.
Franklin admitted that the win over a close friend was bittersweet.
"At one point, Matt hit me with an uppercut, and I thought, "How can you do that to a friend?" Franklin joked.
Dan Henderson (23-7) came to Atlanta on a losing streak, having lost title bouts to light heavyweight Quinton Jackson and middleweight Anderson Silva since moving to UFC with the demise of PRIDE, where he was a champion.
The 38-year-old won with veteran poise and patience, fending off the takedown and submission attempts of Brazilian Rousimar Palhares (17-2) and patiently finding spots for his punches, taking a unanimous decision.
"This opponent was as tough as anybody I faced," Henderson said in his postfight interview with commentator Joe Rogan.
Henderson fought on an early UFC card, before White and his partners Frank and Lorenzo Fertitta bought the company, but spent the next several years elsewhere.
"I haven't had a win in the Octagon in about 10 years, so it feels pretty good," Henderson said. "Hopefully I don't wait that long again."
Nate Marquardt (30-8-2) made quick work of fellow middleweight Martin Kampmann (13-2), stunning the Danish-born fighter with a head kick and threading a few effective punches through Kampmann's arms. Referee Mario Yamasaki stopped the bout at the 1:22 mark.
Welterweight Matt Brown (10-7) won over the crowd with his entrance music selection of The Devil Went Down to Georgia and had the crowd chanting "U-S-A," but he never figured out the unorthodox style of Korean fighter Dong Hyun Kim (11-0-1), who took him down and bloodied the former Ultimate Fighter contender with an elbow late in the third round to seal a split decision that displeased many in the crowd.
On the preliminary card:
•Lightweights: Kurt Pellegrino (18-4) dropped and bloodied Thiago Tavares (17-3) early but tired and atttacked less after taking a poke to the eye in the second round. Pellegrino held on for a unanimous decision.
•Light heavyweights: Tim Boetsch (8-2), whose last fight was a loss to Hamill, floored Mike Patt (15-3) with a straight right in the first round and landed a couple of solid shots on the ground before referee Herb Dean stepped in for the stoppage.
•Middleweights: Jason MacDonald (22-10) recovered from a deep choke, bailed out by the horn at the end of the first round, to submit Jason Lambert (23-9), a former light heavyweight who lost to Evans two years ago, with a choke in the second. MacDonald told Rogan in the Octagon that he could see the screen with the time remaining at the end of the first round. "I can hold my breath for six seconds," he said.
•Welterweights: Brazilian fighter Roan Carneiro (12-8), a recent transplant to Atlanta, had the crowd on his side and wore an "ATL" logo along with ads for an Atlanta pizza restaurant on his shorts. He dominated the first round against Ryo Chonan (15-8), but the Japanese fighter got on top in the next two rounds and took the crowd out of it on his way to a split decision win.
A welterweight bout between Karo Parisyan and Yoshiyuki Yoshida was called off when Parisyan suffered a back injury the week before the fight.