Masters champion Patrick Reed on his mental game during 2018 tournament

Patrick Reed clinched the 2018 Masters Tournament on Sunday by just one stroke. The 27-year-old held off one of the strongest fields in the tournament's history including a late charge from Jordan Spieth and Rickie Fowler to win his first major victory.

"It was just a sigh of relief. To dream about winning the green jacket as a child growing up, you know, having all those putts on the practice greens with all your friends… to have that dream come true is, it's just a surreal moment. It hasn't fully set in yet," Reed said on "CBS This Morning" Tuesday.

It was an exciting finish for viewers with Spieth, who won the Masters back in 2015, pulling even with Reed at one point. Spieth has said he wasn't paying attention to the leader board. That's a notion Reed doesn't exactly buy.

"I knew exactly where everyone was. So I'm the type that I always like to know where I stand, where I'm at," he said. "He might have not been like focusing on the leader board, but you know... you definitely know where you're at.  

As for how he mentally prepared for the game, Reed reminded himself just that – it's only a game.

"My whole motto the entire week was, 'Hey, just do you. Be who you are. Just play golf.' You know, because a lot of times coming into the majors, people overhype them. … And so I tried to basically bring it back down to reality that it's a golf tournament. It's 18 holes."

For Reed, golfing is a family affair. His wife, Justine, caddied for him until she was pregnant with their first child. Then Justine's brother took over.

"She's my rock," he said. "Without her, you know, this wouldn't have happened. I wouldn't be here." 

He added, "She's been there walking practice rounds inside the ropes, helping us, you know, figure out golf courses and our game plans."