JOHANNESBURG -- The main story today is the U.S. meeting Brazil in the final of the Confederations Cup (2:25 p.m. ET, ESPN, Univisión), the first final in a major tournament in the history of U.S. men's soccer. But there is another developing story here.

Soccer governing body FIFA tells SI.com that it is investigating an alleged incident between U.S. midfielder Michael Bradley and referee Jorge Larrionda that took place after the U.S.'s 2-0 upset of Spain in Wednesday's semifinal, according to FIFA spokesman Nicolas Maingot.

Larrionda had sent off Bradley in the 87th minute for a tackle on Spanish midfielder Xabi Alonso. As a result, Bradley--the son of U.S. coach Bob Bradley--is suspended for today's final.

The Spanish daily AS first reported that Bradley had allegedly confronted Larrionda in the tunnel following the game. But that report had no byline and cited no sources. This is the first time FIFA has confirmed that an investigation is taking place.

"FIFA is looking into the matter and cross-checking all available evidence," Maingot wrote to SI.com in an e-mail message. "Therefore, for the moment, we are not in a position to confirm the nature of the incident."

Maingot did confirm that Larrionda filed a match report after the game, per FIFA policy, but the FIFA spokesman added that as long as the investigation is ongoing, it would not reveal the content of the report.

"A decision of the FIFA Disciplinary Committee concerning a possible additional match suspension might come in a couple of days," Maingot wrote.

A U.S. Soccer Federation spokesman had no comment.

If Bradley does receive an additional suspension, it could be applied in terms of matches, days or months, according to Article 19 of the FIFA Disciplinary Code. If FIFA were to apply such a suspension in terms of matches, it would be unlikely to affect Bradley's availability for the U.S.'s important World Cup qualifier against Mexico on August 12. FIFA suspensions are in effect for official FIFA games, which would include the upcoming CONCACAF Gold Cup. Bradley is not on the U.S.'s Gold Cup roster, but he could still serve a potential match suspension (if there is one) during those games.

Larrionda, a FIFA referee from Uruguay, also refereed the U.S.'s World Cup 2006 encounter against Italy, in which he sent off three players (including Americans Pablo Mastroeni and Eddie Pope).

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