The Daily Bagel is your dose of the interesting reporting, writing and quipping from around the Internet.
• Video: Petra Kvitova recaps her up-and-down 2013 season in an interview on CNN World Sport.
• USA Today reports that Mardy Fish, who has struggled with a heart condition for much of the last two seasons, is contemplating professional golf. Should fans expect his official retirement from tennis soon?
• The Tennis Space recaps which doubles teams are splitting and reforming next season. Welcome back, Indo-Pak Express and Nestor/Zimonjic.
• Carl Bialik of The Wall Street Journal spent a week at an umpire academy in Paris. Being a chair umpire is a lot harder than it looks.
They have the best seat in the house but can't watch the match like a fan -- they focus on close calls and trouble spots, rather than spectacular rallies or breathtaking winners.
Students learned that selling a close line call is just as important as making the right call. So, for instance, Ramos advised that calling the score loudly helped.
Confident, clear communication is paramount, with both players. The key is to ensure neither player thinks the other has special influence over your decisions. But it's a fine line between confidence and cockiness, Ramos said. "It's very easy for people to think we are arrogant. We sit up there. That's not a good starting point for having a discussion with somebody."
• Should Serena Williams be doing this? I say no.
• Get to know Dusan Lajovic, No. 117 in ATP rankings, who is stepping in as Serbia's No. 2 for this weekend's Davis Cup final against the Czech Republic.
• Bonus video: An amusing interview with a very deadpan Andy Murray, who makes taking a shot look incredibly awkward (at the 3:50 mark).
• Non-tennis: 10 great full-length concerts on YouTube
. Have a great weekend!