QUEBEC CITY: Canadian southpaw Adonis Stevenson retained his World Boxing Council light-heavyweight world title Saturday with a sixth-round technical knockout of Britain’s Tony Bellew. Stevenson dropped Bellew in the sixth with a heavy left to the jaw. Bellew beat the count, but Stevenson landed another left that sent the challenger staggering into a corner. The champion was unloading again on the defenseless Bellew when referee Michael Griffin called a halt at 1:50 of the round. Haitian-born Stevenson improved to 23-1 with 20 knockouts. He was plainly pleased to have made his point against Bellew after an ill-tempered build-up to the bout.