Washington ? Fifteen years ago, Mike Tyson was a devastating puncher with an aura of invincibility that cloaked him in every match. When he stepped into the ring, it was inevitable that his opponent would get knocked out. It was just matter of what round.

Tyson remains a devastating puncher, and nowadays when he fights, a KO is a certainty. But Tyson could wind up flat on his back just as easily as his opponent. So, when he steps in against Kevin McBride, a 6-6, 271-pound Irish-born behemoth, tonight at the MCI Center, no one is expecting a 10-round decision for either man. It could be like a Wild West gunfight. The first man to draw (or in this case land a clean shot) could wind up knocking out the other.

“When I hit Mike Tyson on the chin it’s going to be like the whole island of Ireland hit him,” McBride boasted this week.

Much has been made of Tyson’s diminished skills over the last decade. If McBride (32-4-1, 27 KOs) were a world-class boxer, along the lines of former champ Lennox Lewis, his threat would carry considerable weight. But McBride isn’t a top-shelf contender and is shaky mentally. He has been consulting a hypnotist in order to boost his confidence and increase his threshold for pain.

“I’m equipped enough to beat Kevin McBride,” said Tyson, whose last victory was a KO at 49 seconds of the first round against Clifford Etienne in 2003. That victory capped a tumultuous week in which Tyson first called off the fight and then showed with a tribal tattoo on the left side of his face.

Tyson has been remarkably mellow leading up to this fight. No outrageous behavior. No profane outbursts. Just plenty of talk about love, respect and child care. Has it dulled Tyson’s fire in the ring? That is one of the intriguing questions going into this match.

Tyson (55-5, 44 KOs) always has had trouble with taller opponents. If McBride had a good jab and decent hand speed, Tyson would have trouble getting inside to work the body.

“Kevin has picked up his speed tremendously,” said Goody Petronelli, McBride’s trainer. “He’s got his combinations working and he’s really worked on speeding up his jab. We’re prepared to go 10 rounds if we have to, but it’s not going to go 10 rounds.”

Tyson is coming off a loss in his last fight. Danny Williams, another set-up opponent, stopped Tyson in the fourth round last July 30 after Tyson tore the medial collateral ligament in his left knee in the first round. So, Tyson has to worry about ring rust – he has fought just once a year for the last four years – and the soundness of his knee when he steps in against McBride.

Jeff Fenech, the former featherweight champ who is training Tyson for the first time, said this is the beginning stage of a building process with Tyson. Fenech is trying to rebuild Tyson into some semblance of the fearsome force that he was 15 years ago. It is a nearly impossible reclamation project because Tyson is almost 39.

Fenech is confident about Tyson’s prospects against McBride. “Mike has done everything he needs to do to win this fight,” Fenech said. “When we walk out of that ring, there will be no excuses.”