Puerto Rican southpaw Lopez improved to 26-0 with his 24th stoppage inside the distance while Lontchi, a Cameroon-born Canadian, fell to 18-1 with two drawn.

Lopez sent Lontchi to the canvas in the second and ninth rounds and the challenger did not leave his corner after the ninth round.

The victory was the fourth by Lopez to defend the crown he won here last June against countryman Daniel Ponce de Leon. Just two months ago, Lopez won on home soil against Gerry Penalosa of the Philippines.

In a super flyweight undercard bout, Mexico's Jorge Arce improved to 52-5 with one drawn with his 40th career knockout, stopping Filipino Fernando Lumacad, 19-2-2, just 35 seconds into the third round.