The only MLS influence in the CONCACAF Champions League semifinals will come from a few of its former employees. Ex-D.C. United striker Nicholas Addlery, former Crew goalie Bill Gaudette and the first of two Northern Irish head coaches hired by Dallas, Colin Clarke, were among the celebrants in San Pedro Sula Wednesday after the USL's Puerto Rico Islanders defeated CD Marathon, 1-0, in the second leg of their quarterfinal series.

The USL-1 Islanders face Mexican club Cruz Azul in the semifinal round, which kicks off in late March. Cruz Azul beat UNAM, 1-0, on Wednesday to win that series, 2-0, on aggregate.

Puerto Rico teetered on the edge for much of the match before prevailing and winning the series, 3-1, on aggregate. Had it conceded a goal and lost, 1-0, it would have been eliminated by the away-goals tiebreaker. Instead it withstood numerous attacks, and broke away just seconds into stoppage time to ice the match.

Addlery, who had the first of two Puerto Rico goals in the first leg, raced onto a through ball and drilled a shot from the edge of the penalty area past the ankles of transfixed goalie Juan Obelar.

Marathon fielded its own MLS representation. Former Fusion striker Saul Martinez nearly won the series for Marathon with a thunderous strike in the 82nd minute that utterly beat Gaudette but crashed off the crossbar.

Gaudette had to limp through the final minutes after taking several hard hits during furious Marathon assaults, yet he and his teammates persevered. His sharp reflexes and confident handling covered what a very resolute back line couldn't deflect, and a disbelieving crowd grew more frantic as Puerto Rico repelled chance after chance.

(Clarke, a native of Newry, Northern Ireland, was head coach of FC Dallas from 2003 to 2006. He was succeeded by countryman Steve Morrow, who was born in Belfast. Clarke took over the Islanders in 2007 after Virginia Beach Mariners, who had hired him two months earlier, folded.)

The USL can claim two representatives in the semifinals, as compared to none for MLS, if Montreal can parlay its 2-0 first-leg edge into a series victory. Montreal would play Atlante, which eliminated the last MLS entrant, Houston, with a 3-0 second-leg win in Cancun Tuesday.

The venue changed, but the flow of play and result didn't. Cruz Azul -- leading its quarterfinal series with Mexico City rival UNAM, 1-0, from the first leg -- dominated Pumas on their own field, and took the second leg by the same 1-0 score Wednesday at Estadio Olimpico Universitario.

Not until Cristian Riveros scored a spectacular goal in the 86th minute did Cruz Azul erase all doubt regarding the outcome, yet Pumas seldom gave their home fans much to shout about and seldom threatened.

With the 2-0 aggregate win, Cruz Azul advanced to the semifinals to play either Montreal Impact or Santos Laguna, which play their second leg Thursday (10 p.m. ET, Fox Soccer Channel, TeleFutura) in Torreon, Mexico. Los Cementeros also extended their unbeaten streak against UNAM to eight games.

UNAM keeper Alejandro Palacios labored through several shaky moments as Cruz Azul cut open his defense numerous times. In the first half, Luis Angel Landin broke through on the left side to fire a shot just wide of the far post, and first-leg scorer Jaime Lozano bounced a header on frame that Palacios bobbled but managed to keep out. The goalie also batted away a Lozano free kick early in the second half.

Constant Cruz Azul attacks paid off in the final minutes when a fatigued UNAM, playing its sixth game in less than three weeks, crumbled again and Edgar Enrique Martini glided clear to hit a clever back-heel to Riveros, who easily belted it past Palacios.

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