The qualifier about being mentally right provides Lopez Sr. with a convenient excuse whenever his son struggles. The sharp performances get credited to the true Teofimo. The flat outings get blamed on emotional distractions, an uncooperative opponent, a difficult weight cut, or other outside factors.

That built-in protection vanishes against Romero on Saturday at T-Mobile Arena in Las Vegas. Teofimo is making his welterweight debut with seven extra pounds available after leaving 140 behind. If boiling down drained him previously, the elite version should show up now.

Romero brings the kind of power that can wreck the entire claim. He looked physically imposing against Ryan Garcia, scoring a second-round knockdown and landing the stronger punches throughout the bout. Teofimo is facing a naturally thicker fighter who hits hard and will not be intimidated by his hand speed.

It is scary to consider what natural junior middleweights and middleweights would do to Teofimo. His father treats quickness like an automatic equalizer against larger, stronger punchers. Teofimo is not a busy operator who dominates entire rounds behind a steady jab. He often looks for single counter shots, resets slowly, and grows frustrated when opponents refuse to trade in the pocket.

Bigger punchers at 154 and 160 would capitalize on those lulls by cutting off the ring, crowding Teofimo, and bullying him to the ropes. Moving into higher divisions will not grant him sudden knockout power or greater punch resistance. The shots coming back will carry considerably more force.

Teofimo generally performs best against aggressive opponents who come forward to trade, which means Romero will offer openings. The trouble starts if Teofimo pauses too often, fires single punches, or gets flustered under heavy pressure. Romero possesses the physical strength to force the action and keep him on his heels.

A defeat in his first bout at 147 pounds would punch a hole through his father’s claim before the fantasies about 154 and 160 even begin. The excuse of making 140 pounds is gone. Teofimo has the seven-pound cushion his father wanted. He must defeat Romero before anyone takes this talk of conquering junior middleweight and middleweight seriously.