Sugar Ray Leonard has beaten every slow-moving opponent so far, and he hasn't had to move much to do it because he has superior eye-hand coordination.

But to beat Thomas Hearns tonight in Las Vegas, Leonard will have to move and punch, and that won't be easy against so tall and hard-hitting a foe.

Leonard has not demonstrated that he can move and punch. In his first fight with Roberto Duran, Leonard tried to prove that he could take it and forgot what boxing is all about.

In the return bout with Duran, Leonard did show some moves but nothing like those necessary to open up Hearns, who will be a well-shielded sniper behind that long, snappy jab. And his right hand will be tucked under his chin.

To beat Hearns, Leonard will have to hit him in the body -- something he does well only when an opponent is tired. Against Wilfred Benitez, Leonard won the title in the last round with several wicked shots to the body.

Against Ayub Kalule, Leonard went for the head again, although his opponent stood flat-footed in front of him. Late in the fight, he landed some hard body shots and Kalule had to call it a night.

Yet Leonard has not shown that he can attack the body effectively, and he will find it almost impossible to bring down his 6-foot-2 1/2 opponent without doing so.

Hearns' 78-inch reach is his biggest asset; it does severe damage and sets up his heavier artillery. His jab is quick and snappy. His overhand right is devastating when it lands solidly. His left hook is more than adequate.

What stops Hearns from being a cinch in this fight is his lack of enthusiasm once an opponent begins to ward off or slip inside his jab.

The sight of him becoming weaker and weaker against a battered Harold Weston cannot be forgotten.

Hearns had given Weston a terrible beating in the first four rounds of their bout two years ago. Weston's eyes were almost shut and he appeared rocky as he came out for the fifth round.

But then Weston began smothering Hearns' jabs and long rights and countering to the body and head. Hearns continued to give ground while his light-punching adversary chased him around the ring. Weston surely would have won that fight if the referee hadn't stopped it in the sixth because of his eyes. Titles aren't won by men who retreat when a damaged opponent punches back.

Hearns also will have to be more accurate than he has been lately.

In his fight with Randy Shields April 25 in Phoenix, Hearns missed too often to beat a sharpshooter of Leonard's caliber. Shields couldn't use his left because of a shoulder injury, but Hearns kept missing with his best punches before finally scoring a 13th-round knockout.

In short, Leonard has not demonstrated the know-how to beat Hearns, and Hearns has not shown all the qualities of a great champion.

Prediction: Hearns will do damage early with his jab but will lose control of the fight around the 10th round. After that, Leonard's basic athletic ability and hand speed will prove decisive.