All four matches in the Mexican Apertura on Saturday ended in draws, with Tigres Monterrey most notably missing the chance to reach the summit as they were held to a 2-2 tie by Queretaro.
Olympiacos beat PAOK Salonika 2-0 to move within two points of the league leaders, AEK Athens climbed to third after a win against Panionios, while Doxa Dramas remain bottom after another defeat.
Olympiacos' defeat at FC Xanthi allowed Panathinaikos, who were 1-0 winners against Atromitos, to reach the Super League summit, while strugglers Doxa Dramas and Levadiakos suffered home losses.
FIFA.com reflects on opening-round action in Argentina and Australia, the frontrunners impressing in Brazil and Mexico, and new leaders emerging in Japan and Korea Republic.
Struggling Mexico and Honduras both took qualifying comfort with home wins over Trinidad and Tobago and El Salvador respectively.
Honduras scored a crucial 3-1 home triumph over Mexico who tasted defeat for the second time in their last three FIFA World Cup qualifiers.