The big crowd prompted speculation that the Phoenix market was ready for big-time soccer on a regular basis.
But even the lure of Libertadores Cup champion Boca Juniors couldn't help promoters of the six-team Copa PanAmericana that opened Monday night.
The Arizona Republic reported that "a few hundred" fans turned out in Glendale of the first night of the tournament. Boca beat Alianza Lima of Peru, 2-0, and Cruz Azul of Mexico tied, 0-0, with Colombia's Deportivo Cali.
Club America of Mexico and FC Caracas of Venezuela are also playing in the tournament.
Global Spectrum, which books events for the University of Phoenix Stadium, had been expecting crowds of 35,000 for each night. Last fall Club America and Chivas of Guadalajara drew 35,000 fans for an exhibition.