LAS VEGAS --- Derrick Lewis was dangerous enough Saturday night with his stand-up striking to force KO artist Roy Nelson to fall back on his grappling roots. "The Black Beast" also did enough damage to earn a split-decision victory, after three rounds.

Scores were 29-28 (twice) and 28-29 for Lewis. Nelson was so upset by the decision that he stormed out of the cage and to the back of the MGM as Lewis conducted his post-fight interview.

Most of Lewis' success came at the start of the first and the end of the third rounds. In the first, he stunned Nelson with punches.

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At the end of the third, Lewis appeared to have Nelson out on his feet with more heavy shots before the final horn sounded. Nelson, however, controlled most of the fight in between those close-calls with numerous takedowns and excellent work against the cage and on the mat.

Lewis was often slowed and frustrated with Nelson's black belt grappling but he never stopped fighting. Time and again he got up after being taken down.

In other instances, referee John McCarthy repeatedly gave Lewis assists with separations from the clinch against the clinch when he was unable to free himself from Nelson's grasp. In both cases, Lewis made the most of his opportunities and swung hard until the end.

To his credit, Lewis was happy with the win but not satisfied. "I want to rematch Roy Nelson," he said, afterwards.

"I don't like winning by decision. It is what it is."