LAS VEGAS – Yoenis Tellez’s gamble paid off Saturday night in the most appropriate place.

The 23-year-old junior middleweight prospect knocked out experienced contender Sergio Garcia in the third round of just the sixth professional fight of Tellez’s pro career on the Errol Spence Jr.-Terence Crawford undercard at T-Mobile Arena. Tellez (6-0, 5 KOs) knocked Garcia to the canvas to punctuate an unusual sequence that eventually led referee Robert Hoyle to halt their scheduled 10-round fight.

The Cuban-born Tellez, who took this step up in competition on less than three weeks’ notice, hurt Garcia with a right hand that sent Garcia into a squatting position just before the midway mark of the third round. Garcia never went all the way down, though, thus Tellez drilled him with another right hand that knocked him flat on his back before Hoyle could intervene.

Garcia argued that Tellez shouldn’t have been allowed to hit him when he sprung back to his feet. Once the action resumed, Tellez drilled Garcia with several additional right hands that led Hoyle to step between them and halt the action at 2:02 of the third round.

Spain’s Garcia (34-3, 14 KOs) lost by knockout for the first time in his 11-year, 37-fight professional career. The 30-year-old Garcia’s only previous losses were decision defeats to former 154-pound champions Tony Harrison and Sebastian Fundora.

Garcia was supposed to face southpaw Jesus Ramos, but Tellez replaced Ramos (20-0, 16 KOs) on short notice once Ramos suffered a hand injury during training camp.

In the round before the knockout, a left-right combination by Tellez temporarily stopped Garcia from punching with about 40 seconds on the clock in the second round. Garcia connected with a right uppercut about 20 seconds into the second round.

Garcia pressed the action during the first round, when Tellez mostly worked off his jab.

Hoyle warned Garcia for hitting Tellez twice behind his head barely a minute into the first round. Garcia snuck a right uppercut between Tellez’s gloves several seconds earlier.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.