Taking it to Thomas from the opening round, the 28-year-old Davis, 22-4-2 with 17 knockouts, unleashed a beating on his opponent before stopping him at 49 seconds of round five before an estimated crowd of 2.000 Saturday at Reno Events Center.
The bout wasn't televised on HBO Boxing After Dark and was on the undercard of the Paul Williams-Sharmba Mitchell main event. Williams, nicknamed "The Punisher," lived up to his sobriquet, knocking down Mitchell four times on the way to a four-round stoppage.
The 5-foot-7, 205-pound Davis entered the ring with bad intentions, giving Thomas a wild stare during the pre-fight instructions. Davis, who stopped Thomas in their first meeting in May 2000, caught his opponent with a right hand that sent his 6-4, 196-pound opponent to the canvas for a two-count near the end of the first round.
Davis pressed the attack in the second, rocking Thomas, 16-6-2 (14), with another big right, and threw a high volume of punches in the third before slowing down in the fourth.
Davis landed a big right on the Chicagoan to open the fifth before landing a flurry of punches that prompted referee Kenny Bayless to wave it off.
"He was trying too hard for the crowd, trying to make a good showing," said Kelvin's brother-trainer-manager Kelly Davis. "I knew this guy would be a lot tougher this time and if Kelvin tried to catch him with the same shot, it wouldn't happen."
Although pleased with outcome, Kelly said Kelvin - who pounded Thomas' body with wicked combinations - could've done more.
"I wanted more body shots," Kelly said. "His jab was a little off. He was trying to knock the man out. But (Kelvin) slipped (punches) pretty good."
Kelly said he was impressed the way Thomas absorbed the beating and finished the fight on his feet.
"He showed massive heart," Kelly said. "The shots were sounding off. He's a different fighter now."
Kelvin credited his brother for getting him in shape for Thomas.
""t felt good. My brother got me really prepared for the fight," Kelvin said. "It's a good feeling to be back in Reno. First, I give credit to God, otherwise I wouldn't be here. I got saved nine months ago."
Davis said his injured left biceps muscle and his right hand - on which he had surgery last year - have healed alongside his mental state.
He used that right hand to good effect in the fifth, drilling Thomas with a right uppercut which precipitated his fight-ending assault.
"I unleashed a combination, but I didn't know how bad he was hurt," Davis said. "I caught him with a left hook. I still had more to give to him and I wanted to see him slide down on the ground, but I wasn't able to."
After climbing up on the ropes in a corner to better receive the crowd's applause, Davis leaned over and traded fist bumps with former heavyweight champion and HBO commentator Lennox Lewis, fellow commentator Max Kellerman and unofficial fight judge Harold Lederman.
"I met Lennox Lewis in New York," Davis said. "In Las Vegas, he goes, 'Hello, Champion.' That made my day. He and Mike Tyson are my greatest champions."
Next up for Davis is Ernest Matteen on Sept. 21, in St. Louis.
"One thing with (Kelvin)," said Kelly Davis, "is he's always in an exciting fight. He's too short to do anything else. He'll go down smoking or take the guy out."
Against Mitchell, Williams was able to take his man out.
Now 31-0 (23), the 25-year-old Williams, 146 1/2, took advantage of a massive height, reach and power advantage to stop the two-time former junior welterweight champion at 2:57 of the fourth round, in which he dropped his smaller opponent three times.
The 6-foot-1 Williams, who has a 79-inch reach, dropped Mitchell, also 146 1/2, for the first time in the third round with a pair of left crosses.
The 35-year-old Mitchell, who is 5-7, came out aggressively, but could do nothing will Williams, who came out swinging in the fourth. Williams, of Aiken, S.C., was able to connect with several uppercuts in close against Mitchell and a left cross-right hook sent his opponent down in the fourth.
Another left-right dropped Mitchell, 57-5 (30), for a third time and after a big flurry another left-right sent Mitchell down for the fourth and final time as ref Vic Drakulich counted to 10 at the 2:57 mark.
"He came to fight," said NABO beltholder Williams, who according to promoter Dan Goossen will meet WBO titlist Antonio Margarito in December after the sanctioning body mandated the bout Saturday. "He tried to fight and landed little body shots and stuff, but he got too close to me."
Margarito was scheduled to meet Joshua Clottey in December.
"I'm glad about that," Williams said of the announcement. "I've been calling him out to meet No. 1 (Williams)."
Asked how much of his talent he got to display against Mitchell, Williams was all smiles.
"That's not even the tip of the iceberg," he said. "No, sir. If he would've come out with some sweet stuff, my skill level could've jumped another level."
As it turned out, that was all the skill he needed.
"He was too tall," said Mitchell, who indicated that he would likely retire now. "I'm so used to boxing guys who use a 1-2. He locked up my arms. I couldn't get punches in, but he was still able to whip in punches. I take nothing away from him."
In other bouts:
xx-Chris Arreola, 241, Riverside, Calif., improved to 17-0 (15), with a fourth-round TKO over Damian Norris, 207, Las Vegas via Cuba. Arreola was able to mix up his punches and turned it on in the fourth, landing an overhand right and a pair of left-rights before landing a right that dropped Norris, 8-2 (6) on his face.
Arreola landed another assortment of punches when referee Jay Nady stopped it at 2:59.
xx-Eddie Chambers, 214, Homewood, Pa., ran his record to 27-0 (15), when he stopped Domonic Jenkins, 214, Dallas, Texas, at 2:17 of the fifth round.
Jenkins, 9-6-1 (3) was stung by several combinations in the fifth, but looked to be able to go on and wasn't in any distress when Nady called a halt to the affair.
Chambers countered throughout the bout, landing occasional hard rights and left hooks. Jenkins looked to take the first round with his aggression and work-rate, but some good counterpunches took away his initiative the rest of the way.
xx-Ty Barnett upped his record to 8-0 (6) after dropping Ruben Jacoby with a left hook in the first round. Jacoby, now 0-1, got up after tasting the canvas but Bayless deemed him unfit to continue.
Jacoby, 135, of Colorado Springs, Colo., came after Barnett, 134, Washington, D.C., to begin the match, but ran into several hard right hands before the left ended the bout at 2:09.
xx-Maxell Taylor, 154, Baltimore, Md., was in the only fight on the card to go the distance, taking a unanimous four-round decision over Oscar Gonzalez Jr., 155, of Tampa, Fla.
Southpaw Taylor improved to 13-2-1 (5) by boxing smartly against Gonzalez, whose record dipped to 9-6-1 (3). The scores were 40-36 (twice) and 39-37.