Omar Gonzalez headed in a David Beckham corner in the 38th minute to set Los Angeles Galaxy on its way to a 2-0 victory over Costa Rica's Alajuelense on Thursday, meaning U.S. clubs now top all four groups in the CONCACAF Champions League after two rounds of games.

Los Angeles' Group A rivals Morelia of Mexico eased to a 4-0 home win against Honduran team Motagua and moved into second place, level on three points with Alajuelense.

In Group C games, Dallas beat Toronto 1-0 to remain in first place in the group, while Panamanian side Tauro held on for a 0-0 draw at home against Mexican champions Pumas UNAM despite going down to 10 men in the first half.

In California, Robbie Keane made his second appearance for LA Galaxy since signing from Tottenham, starting alongside Beckham and U.S. international Landon Donovan in an attacking lineup.

Beckham was also involved in the second goal on 77 minutes, sliding a through pass to Sean Franklin who crossed the ball for Chris Barrett to tap in.

With two minutes remaining, Los Angeles midfielder Juninho was sent off and will miss the team's trip to Morelia in the next round of matches.

In Mexico, Morelia easily overcame Motagua with a goal in the first half from Rafa Marquez Lugo and goals after the break from Joao Rojas, Diego Jimenez and Gerardo Lugo. Morelia is three points behind L.A. Galaxy.

Dallas' game in Toronto was suspended due to lightning at halftime Wednesday with the score 1-0 to the Texan team.

In the replay Thursday morning, a first half header by Jack Stewart was good enough to win the three points for Dallas, which now has six points from its first two games after becoming the first Major League soccer side to win in Mexico in the competition by defeating Pumas last week.

Toronto remains second in Group C on three points with Pumas and Tauro both on one point following their scoreless draw. Pumas again played an understrength team.

The third round of matches in the principal club competition in North and Central America and the Caribbean takes place on Sept. 13, 14 and 15.

The winner of the regional tournament earns a place in the Club World Cup to compete against the other continental champions.

Monterrey of Mexico is the current title holder.