Dustin Johnson, Paulina Gretzky welcome 2nd child

Defending U.S. Open champion Dustin Johnson is a father for the second time after his fiancee, Paulina Gretzky, gave birth to a boy Monday.

Gretzky delivered the boy, whose name has yet to be revealed, via a scheduled C-section, according to ESPN's Ian O'Connor - allowing Johnson to fly to Erin Hills in Wisconsin on Tuesday.

The couple's first son, Tatum, was born in January 2015.