Daily Bagel: The men prep for ATP Finals play with selfies in suits

The Daily Bagel is your dose of the interesting reporting, writing and quipping from around the Internet.

• From Christopher Clarey: On Roger Federer'sremarkable improvement at the ripe old age of 33. 

• And on that note, a mesmerizing video of Federer lobbing everyone:

[youtube=http://youtu.be/WHSRM847RaY]

• Surprising news: Simona Halep has decided to split with coach Wim Fissette. 

• Lindsay Davenport has signed on to work with Madison Keys during the off-season. 

• Tomas Berdych is tweeting up a selfie-storm at the World Tour Finals:

• The ATP and WTA Finals, compared:

• WTA Backspin has an in-depth round-up of how the rankings shook out this year. 

• The Washington Post profiles Venus Williams' interior design firm. 

• Andy Murray is now a global ambassador for the World Wildlife Fund:

• Lastly, let's just check in on how Maria Sharapova's off-season is going: