It was like lambs to the slaughter as Jamaica’s young Reggae Boyz started the Concacaf Men's Under-20 Championship with a dismal performance and were mauled 9-0 by United States at the Miguel Aleman Valdez Stadium in Mexico on Friday.

The Jamaicans, who would have entered the tournament confident of a good performance, did little to show that they will be competitive in the tournament, which serves as a qualifier for next year’s Under-20 World Cup in Chile.

With the win, reigning champions United States took pole position on three points, ahead of Cuba and Costa Rica, who played out a 1-1 stalemate in the curtain-raiser of the Group A double-header.

Jamaica’s young Reggae Boyz had no response to the onslaught of three-time champions United States, who, in a frantic start, raced to a 4-0 lead inside 21 minutes.

In fact, Jamaica’s lone effort on target was from an ambitious 25th-minute freekick from captain Adrian Reid Jr, driven along the wet surface from well over 30 yards out.

David Vazquez grabbed an early brace in the 2^nd and 3^rd minutes, as he opened the scoring with an easy finish from deep inside the box, and he later drove home a left-footer in similar fashion.

Pedro Soma struck with a left-footed strike of his own in the 16th to extend United States lead, and he too completed a brace in the 20th with another left-footed hit inside the box.

Not even a slew of early substitutions by Jamaica’s head coach, Jerome Waite, could stop the carnage, as Cruz Medina capitalised on their sloppy defending to finish off a loose ball and put United States 5-0 up at the break.

As the evening rains continued to drizzle, the one-way traffic continued on the resumption when Marcos Zambrano struck in the 54^th as United States maintained their offensive efficiency.

Ruben Ramos scored in the 67th to make it seven, before Nimfasha Berchimas added another in the 77th.

Nikolas Tsakiris then capped the win with a close range effort in the 90+1 minute.

Earlier, Samuel Rodriguez’s eight-minute penalty put Cuba in front, but the Spanish-speaking Caribbean island couldn’t maintain the lead, as Esteban Cruz (52nd) earned Costa Rica a share of the spoils.

It was a contest that could have gone either way, but for excellent glove work by Cuba’s Yurdy Hodelin and his Costa Rican counterpart Berny Rojas, as both teams had their fair share of chances.

After Leonardo Alfaro’s 23^rd minute strike for Costa Rica came back off the crossbar, Hodelin kept out Andy Rojas’ 30th-minute penalty kick.

Costa Rica’s custodian, Berny Rojas, came up big twice to deny Aniel Casanova and Cristian Mendoza in quick succession.

Action in Group A will resume on Monday with the young Reggae Boyz to lock horns with Costa Rica, while Cuba will face the United States in the feature contest at the same venue.