*NYSNC-gone-solo pop star Justin Timberlake is having a hard time saying "Bye Bye Bye" to love triangles.

Only a few weeks after rumors surfaced that his two-year relationship with Cameron Diaz ended last month because of a fling with Scarlett Johansson, Timberlake has been spotted seesawing between spending Super Bowl weekend with ScarJo and snuggling up to Jessica Biel on the ski slopes, according to celebrity gossipmongers.

Timberlake and Biel were caught cozying up last month during the Sundance Film Festival in Park City, Utah, but this past weekend Biel was nowhere to be seen.

Instead, Timberlake and Johansson, both in Miami for the Super Bowl, got hot and heavy at the Mokai after-party, The New York Post and In Touch Weekly reported.

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Post spies saw the pair dancing, talking and holding hands all night.

"As they left through the back, Justin was leaning against the wall and Scarlett came up, leaned into him and did a sexy little dance, grinding into his body," said Post stargazers.

In Touch insiders dished about a 3 a.m. "nightcap" Timberlake and Johansson had at his bungalow in the Delano Hotel, where he was reportedly staying for the big game.

Timberlake's spokesman, celebrity PR powerhouse Ken Sunshine, had no comment about the sightings. Johansson's rep didn't, either.

Johansson's people did confirm that the actress just landed a year's lease on a $1.5 million South Beach condo, worth about $50,000, according to the Post.

Timberlake, who turned 26 on Jan. 31, rose to fame as a member of R&B boy band *NSYNC and the former boyfriend of Britney Spears. He won Grammys for his first solo album "Justified" and hit single "Cry Me a River" and released follow-up "FutureSex/LoveSounds" last year, featuring chart-topper "SexyBack."

Johansson, 22, became a household name after starring in the Sofia Coppola film "Lost in Translation" opposite Bill Murray. More recent roles were in "Match Point" and "The Black Dhalia." She just finished shooting "The Nanny Diaries."

Biel, 24, is best known for her role in the TV series "7th Heaven" and has had big-screen roles in "The Illusionist" and "The Rules of Attraction."

Diaz, 34, starred in "The Holiday," "Gangs of New York," the "Charlie's Angels" movies, "There's Something About Mary" and numerous other films.

Timberlake and Diaz are the voices behind two main characters in the animated movie "Shrek the Third," due out this year.

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