United States prosecutors have extradited a top FIFA executive arrested in Switzerland as part of their investigation of corruption in world soccer, and on Thursday they revealed that they had been engaged in plea negotiations with another defendant charged in the case.

Jeffrey Webb, who was arrested in an early-morning raid in Switzerland in May, agreed to extradition and is currently in the United States, a person who has been briefed on the investigation confirmed Thursday.

Mr. Webb is the first of the 14 soccer officials and marketing executives indicted in May to be sent to the United States from abroad. The Swiss Justice Department said last week that one of the seven FIFA officials arrested and detained in Switzerland had agreed to be extradited in a simplified procedure but did not name the official.

Until his indictment, Mr. Webb, a native of the Cayman Islands, had been the president of Concacaf, the regional confederation representing Central and North America and the Caribbean. He was also a vice president of FIFA, and he was known for calling for reform within the organization. The indictment charged that he asked for bribes in return for the lucrative television deals regarding soccer games.