Biyarslanov, 28, applied pressure, using a fencing-like jab that targeted Espinosa’s body. In the third round, Espinosa, of Mexico City, switched to southpaw after eating right hooks, and he managed to rock Biyarslanov with a left hook twice in the round, forcing him backward. But it didn’t keep Biyarslanov from knocking him down twice in the round, and Espinosa would be dropped again by a straight left hand in the fourth round.
