The Daily Bagel is your dose of the interesting reporting, writing and quipping from around the Internet.
• Video: Andrea Petkovic wishes you a Merry Christmas in the only way Petkorazzi could.
• Rafael Nadal isn't the only high-profile player to pull out of an exhibition this week (Nicolas Almagro took his place at the event in Abu Dhabi). Maria Sharapova will skip one in Seoul because of neck pain. The world No. 2 was due to face Caroline Wozniacki before doctors ordered her to rest.
• Sport360 reports that Abu Dhabi organizers approached Roger Federer to replace Nadal but the Swiss turned them down. A funny turn of events given the tournament's initial position that Federer wasn't originally invited to play because it wanted to focus on current and past champions. Egg? Meet face.
• Juan Martin del Potro will skip the first-round Davis Cup tie between Argentina and Germany.
• Who doesn't love a good tennis quiz? Kamakshi Tandon is the quizmaster for ESPN.com.
• The Atlantic predicts 2013 will be a transition year in men's tennis, with four different players winning the four Slams. But wait ... didn't that already happen this year?
• Nadal launched an iPhone app. He's also rumored to be following in Federer's footsteps and leaving IMG.
• Victoria Azarenka is on her way to Thailand for an exhibition.
• Non-tennis: As one who doesn't worship at the church of NFL RedZone, I appreciated Will Leitch's take on the ADD-inducing program.