The football star-turned-NBC Today show-correspondent left his wife of 11 years for the 23-year-old blonde, who also worked at the network's headquarters, sources said.
Johnson, a model-thin bombshell, was photographed sitting next to Tiki last month at a Washington, D.C., screening of a documentary on Senegal that he hosted for the Travel Channel. Sources believe Johnson also accompanied Tiki to Senegal for the filming late last year, when Ginny was three months pregnant.
The affair is particularly stunning in light of the athlete's long-standing disdain for his philandering father.
"I don't give a (bleep) that the relationship didn't work," he said of his parents' split in a 2004 interview with the Post. "Not only did he abandon her, I felt like he abandoned us for a lot of our lives. I have a hard time forgiving that."
His confidants were shocked.
"He was always the nice guy with a million-dollar smile," a family friend said.
"After 11 years of marriage, Ginny and I have decided to separate," he said.
"This decision was a painful one, but we are moving forward amicably and will continue to work together to raise our children with the love and dedication they have always known."
His spokesman declined to comment.
Ginny Barber is a former fashion publicist and full-time mom to the couple's two sons -- A.J., 7, and Chason, 6. She, too, declined to comment.
Johnson could be seen posing with a smiling gal pal in a pic on her MySpace page. The two are wearing red short shorts and Giants jerseys emblazoned with Barber's No. 21.
Tiki and Ginny Barber began dating 16 years ago when both were students at the University of Virginia.
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