Victory over Tellez was the first time Barrett had returned to the ring since the first loss of his professional career, a majority decision against Ronnie Clark in February.
In the opening round, Barrett used his reach advantage to control, keeping Tellez at bay with solid jabs.
Moving into the second round, Zelfa continued to control the fight with an effective jab, landing some clean uppercuts to the body in the final minute of the second round.
In the third, Barrett continued to control the fight with a bludgeoning jab, which had left Tellez sporting a visibly swollen and somewhat bloodied nose.
Barrett was coasting. However, Tellez continued to walk Barrett down in the fourth, giving it his all when on the inside and landing on occasion at close quarters.
Early in round six, Barrett was caught with an extremely low blow and took a moment time to recover in a neutral corner. As the round progressed, Zelfa exacted some revenge on Tellez, unloading on the inside and landing a number of punishing body shots, which hurt Tellez. The Spanish based fighter was convinced they were low and looked to the referee in agony, however, his protests were ignored and the crowd were not convinced either.
In the seventh Tellez again complained of low blows, taking a knee in the corner, as the referee warned Zefla to watch his shots. Once Tellez has recovered, Barrett continued to work the body, while also utilising the jab effectively and mixing in both left and right hooks to the head of Tellez.
As we reached the midway stage of the seventh round, Barrett landed what was deemed another low blow, and was given a final warning by the referee. By this point in the contest, Tellez was keeping a high guard, and was not keen to walk Barrett down.
The final round was a much more cautious affair from both fighters, who seemed happy to coast the final three minutes with none of the action we saw in the sixth and seventh.