CHERRY HILLS VILLAGE, Colo. -- Michael Weaver never stopped believing it was his day, even after his big lead started to slip away.
Buoyed by four birdies on the front nine, including a 50-foot putt on the par-3 eighth, Weaver shook off Justin Thomas' late run for a 3-and-2 victory Saturday and a shot in the U.S. Amateur final at Cherry Hills.
"Whenever you make a putt like that, it's a little bit of luck," Weaver said. "But you know, it was just kind of one of those days when it's your day. It's just going to go in. That's how the whole front nine kind of was. I really felt like I couldn't do anything wrong. It was just all going my way."
Weaver will face Steven Fox of Hendersonville, Tenn., on Sunday in the 36-hole championship match.
Fox, a senior at Tennessee-Chattanooga, beat Brandon Hagy, Weaver's teammate at the University of California, 2-up.
The 21-year-old Weaver, from Fresno, Calif., opened his semifinal match with Thomas with three consecutive birdies to go 2-up. He stretched his lead to 5-up after the 10th hole and withstood a rally by Thomas, an Alabama freshman who won three of four holes to get within two of Weaver.
"I just kept hitting good shots and kept giving myself chances," Weaver said. "That really helped me out a lot because I needed it. Justin came around a little bit and I slipped a little bit. But to start like that in the biggest match I've ever played in, that was an awesome feeling."
Weaver maintained his composure in the face of Thomas' late charge, and he said that's how he held him off.
"I just tried to forget that I had lost three of the last four holes to him," Weaver said. "I really just focused like I had done all day, went through my routine the same way and hit a good shot. I didn't try to pump myself up or anything like that. That's not how I am, I guess."
Setting himself up on the green with a clutch chip shot, Weaver secured the win when he knocked in a 6-foot birdie putt on the 451-yard, par-4 16th hole as Thomas just missed a 15-foot birdie putt.
He thrust his arms in the air in celebration and got a hug from his father, Bill Weaver, who has caddied for his son throughout the weeklong tournament. Both wiped away tears of joy.
"I'm so proud of him," Bill Weaver said. "He's a very strong individual, no give-up in him. He just gutted it out."
Michael Weaver got choked up again later, recalling his deciding putt to get to the championship round and sharing it with his father.
"That was pretty special," he said. "I'll remember that forever. I'm so excited. My dad caddies for me all the time. I'm so excited he could be here to be part of this. I owe him a lot. He's supported me all along, everything I needed and I wouldn't be here without him."
Thomas said Weaver simply outplayed him on the front nine and the deficit proved too much to overcome.
"I didn't battle through it well enough," Thomas said. "Although it hurts a lot to lose, especially this late in the tournament, it's a lot better to get beat than to lose."
The championship Sunday brings together two long shots from an original field of 312 players from 43 states and 20 countries that began the stroke play qualifying on Monday. Both Fox and Weaver emerged from a playoff at the end of two days of qualifying to win their spots in the 64-player match-play field. Fox was the No. 63 seed and Weaver the No. 60 seed.
Along the way, Weaver had to get past Thomas, the Jack Nicklaus Award winner as the nation's top college player. Fox advanced to the semifinals by defeating Chris Williams, the University of Washington star who was the top-ranked amateur.
"Whether you're No. 1 or 64, you always have a chance," Fox said. "And it's awesome how we survived a playoff and got this far. It's really unreal."
On Saturday, Fox weathered a tightly contested match with Hagy that was all square as late as the 14th hole. Fox made par on No. 15, and went 1 up when Hagy missed a 10-foot putt for a bogey.
They matched each other on the next two holes. On the 472-yard, par-4 18th, Fox used a 4-iron to drive his second shot 206 yards, landing it within 6 feet of the hole.
"Best shot of my life," Fox said.
It also impressed Hagy.
"That was a spectacular shot," Hagy said. "Very clutch. And my shot, I hit it right at the flag. It looked really good and just went a little too far."
Hagy overshot the hole on his second shot, rolling the ball to the back of the green. His try for a long birdie putt was wide, and it gave Fox the 2-up victory.
Then his phone started ringing.
"It's been going off like crazy," Fox said. "There's so many people back home backing me. I mean, it's just awesome. Without them I wouldn't be here, especially my family. They're all rooting for me. It's an unbelievable feeling. It just puts a smile on your face."