The ornamental requirements of the ninth Pan American Games were fulfilled more or less on schedule today, as President Luis Herrera Campins of Venezuela officially declared the competition underway during an impressive opening ceremony at packed Estadio Olimpico.

The flags of the Pan American Sports Organization were transferred formally from Puerto Rico to Venezuela and the traditional flame was lighted by Francisco Rodriguez, a two-time Pan American boxing gold medalist for the host nation.

Carrying the U.S. flag in the parade of athletes from 32 competing countries was Denise Curry, a member of the 1979 silver medalist basketball team who is back for another try at the gold. Although banners with the names of 35 nations were displayed, no athletes were present from Antigua, Bolivia or El Salvador.

The parade was colorful and equally impressive was a parasol section of about 3,000 persons who executed intricate designs.

All the competitors received generous applause.

The start of competition on Monday was left in considerable confusion when failure of some athletes to arrive and protests over scheduling forced redraws in many areas.

Curry and her teammates, who are favored to take the gold away from Cuba, were scheduled to begin play Monday morning against Peru. The Peruvians withdrew today, however, and now the first U.S. game is set for Friday against Brazil.

The soccer draw originally listed the 12 teams in four pools of three, which guaranteed only two games to each participant and made a critical item of Monday's U.S.-Brazil contest.

Many complaints prompted a redraw into three pools of four, thereby assuring each entry of at least three games. When soccer officials completed the new alignment tonight, the U.S. found itself paired with Guatemala Monday at 10 a.m.

In other competition Monday, the United States plays the Dominican Republic in baseball, Mexico in men's basketball, Canada in field hockey, the Netherlands Antilles in men's softball and Puerto Rico in women's softball.