Dingman and Uchitel hooked up on two occasions over a two-week period in October 2009 while they were staying together at the Miami home of investor Chris Barish, reports TMZ.
Uchitel allegedly disclosed details of her flings with Dingman and Woods to Barish, whose then-girlfriend Jen Madden eventually leaked news of Woods's affair to the National Enquirer in November 2009.
Woods has never expressly acknowledged a relationship with Uchitel, but did admit that he'd betrayed his moral code while married to Nordegren.
Friends of Dingman deny that he ever spent time with Uchitel, but his current girlfriend and Woods's ex-wife Nordegren is said to be very upset over the report.
Reps for Nordegren and Uchitel haven't yet offered any public comment.
Nordegren has apparently been dating Dingman for several months and recently took him on a tour of her native Sweden.
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