Masback, a former 3:52 miler and Princeton grad, told USATF of his decision on Wednesday. He will not leave his position immediately, but no date for his departure has been announced. No replacement for Masback has been chosen.

At Nike, which is a major sponsor of USATF, Masback's role will be to negotiate and manage Nike's contractual relationships with athletes, sports leagues, federations and teams around the world.

"My goal was to have an organization that was as good in terms of quality as our athletes," Masback told the Associated Press. "That's a very high goal. We didn't make it, but I think we made progress toward it."

"Craig has been a great leader of our sport," said  USTF President Bill Roe. "As a former athlete, he understood what would make a difference for our athletes and coaches. As a businessman and lawyer, he helped professionalize our operation at every level. We wish him well at Nike."

Masback said now is a good time to make a change. "We're just in a great position," he said. "When I started, we owed $3 1/2 million. Now we have $3 1/2 million in the bank. All the programs are in place. All the plans are in place for a great Olympic trials, a great training camp and a great Olympics."