Paulina Gretzky Gives Birth, Planned C-Section Before U.S. Open

Dustin Johnson's having a busy week -- his fiancee, Paulina Gretzky, gave birth on Monday ... and then he flew out to Wisconsin for the U.S. open on Tuesday -- and it's all part of the family plan.

With Paulina ready to pop, the couple planned for a C-section delivery at an L.A. hospital on Monday -- giving Johnson enough time to attend the birth and still make it to the golf tourney, which starts Thursday.

Everything went according to plan, according to ESPN's Ian O'Connor, who says Paulina delivered a bouncing baby boy on Monday. The couple picked the name River Jones Johnson.

Sources tell TMZ Sports Dustin and Wayne Gretzky were both at the hospital for the special moment.

The very next day, DJ hopped on a flight to Erin, Wisconsin to gear up for the U.S. Open with a clear head -- knowing Paulina and baby are happy and healthy back home.

Our Erin, Wisconsin sources (yeah, we got those) tell us Dustin appeared focused on golf and confident when he got to Wisconsin -- but he's clearly pumped about having his 2nd kid.