Former world champion Barry McGuigan was overwhelmed by Chris Billam-Smith's stunning upset of Lawrence Okolie.

Last month in Bournemouth, Billam-Smith pulled off a shocker when he dropped Okolie three times to secure the WBO cruiserweight world title with a twelve round decision win.

Okolie was doing well in the first three round - and then the entire fight was turned upside down when Billam-Smith landed a big left hand in the fourth to drop Okolie for the first time in his career. Okolie would later go down in the tenth and eleventh.

Billam-Smith and Okolie were former sparring partners, when the two boxers shared the same head trainer, McGuigan's son, Shane McGuigan.

Last year, Okolie would hire veteran coach SugarHill Steward.

"Okolie always felt he got the better of the many sparring sessions they shared when Lawrence was in our stable. There are plenty who look unbelievable in sparring yet when they fight the magic isn’t there. Then you have boys who look pedestrian in sparring who come alive on the big night. Billam-Smith is of the latter variety," Barry McGuigan explained to The Mirror.

McGuigan felt Okolie was unable to adjust after tasting Billam-Smith's power in the fourth round. He believes Okolie only knew one way to react, which is to hold Billam-Smith when they got too close.

"The fourth round changed everything. Tactically, he was perfect in the first three, throwing long and short hooks from an upright position to catch Okolie on the chin. Okolie couldn’t read him. I was sitting beside Joshua Buatsi. He must have needed treatment to his left ear after listening to me screaming all night," Barry McGuigan said.

"Chris slipped to the left and threw a long upward left hook, hit Okolie on the cheekbone and dropped him. That changed the fight. If Okolie was conscious of getting hit beforehand it was far worse from that point forward, grabbing the whole time. Referee Marcus McDonald was brilliant. He warned Okolie repeatedly. He could have thrown him out, but he wanted to give the fight every chance.

"Okolie is so strong and stops you working because he is so concerned about what is coming back. And it then becomes and ugly fight. But Chris coped well and after the first knockdown he made Okolie’s legs dip at least five times."

A rematch is likely in the future, as Okolie intends to exercise an immediate rematch clause.