He'd played Riviera Country Club many times, never with a $1.18-million purse at stake, and watched the Northern Trust Open as a spectator. He remembers, as a fan, standing 10 feet from 2001 winner Robert Allenby.
Merrick is now 30, though, and was growing older by the minute when he teed up this week to face all the big names he could never defeat: Phil Mickelson, Bill Haas, Luke Donald.
So it was a rush the size of Mt. Rushmore on Sunday when Merrick walked off the grounds, a few miles from Pauley Pavilion, with his first tour trophy.
How about a UCLA eight-clap?
Merrick outlasted another feel-good story, Charlie Beljan, on the second playoff hole to escape with the victory.
Merrick won with rounds of 68-66-70-69 and then promised that the first celebratory round was on him.
Forgive his eyes for welling up like a backed-up sink as he waited for reality to sink in.
"I live 45 minutes away," he said. "I went to school across the freeway at UCLA. I've been to this tournament more than any other growing up and this is my first win. The laundry list goes on and on and, yeah, it's cool."
Merrick became the first Los Angeles County native to win the event. Corey Pavin, a two-time winner and also a former UCLA Bruin, was born in Oxnard, in Ventura County.
Merrick and Beljan finished regulation at 11-under-par 273, with Beljan needing an 18-foot putt on No. 18 to get in playoff position.
Merrick and Beljan returned to 18, where both made par on the first playoff hole, then trudged off to the diabolical, 315-yard par-four 10th.
This is the hole where heroes and fools are made. Last year, Haas rolled in a 45-foot birdie putt to win a playoff on the second hole against Mickelson and Keegan Bradley.
Sunday, Merrick took the safe route, laying up with a three-iron while Beljan chose to wind-up blast his drive, which went left into thick rough.
Merrick wedged a second shot to the green and two-putted for par, then watched Beljan try to slither home a downhill four-footer to extend the playoff.
Beljan yanked the putt left, and that meant merriment for Merrick.
This will be remembered as the Northern Trust Open everyone but the groundskeeper had a chance to win.
Haas, Fredrik Jacobson and Charl Schwartzel finished at 10-under 274 and kicked themselves all the way to the parking lot.
Haas, the defending champion, had a three-shot lead to start the day, but it didn't last. He shot one over on the front and carded four straight 5s to start the back nine on his way to a two-over 73. Haas rallied too late with birdies on his last two holes, coming within about six feet of an eagle hole-out on 18 that would have put him in the playoff.
"A three-shot lead at one of the best tournaments of the year is a great opportunity that I squandered," Haas said.
He wasn't the only one.
Jacobson birdied 15 and 16 and appeared in prime winning position before he left a 12-foot birdie putt at 17 short and left. Then he missed a short par putt on the 18th that would have put him in the playoff.
"The last putt wasn't very good," he said, "but it is what it is."
Schwartzel, playing in the final group behind Jacobson and Merrick, missed a 10-foot birdie putt at No. 16 and a six-footer at 17, and still had a chance to make the playoff before missing a 20-footer at 18.
"I hit some good putts," Schwartzel said. "The greens were getting really bouncy and they were fast."
Hunter Mahan took the tournament lead on his back nine only to play three over on his final four holes and finish tied for eighth.
In the end, they all cleared out for Merrick.
Maybe, in the end, it was just his day.
Merrick pushed his drive on the par-five 17th into a fairway bunker and tugged his second shot left, where it came to rest behind two trees.
Jacobson, meanwhile, had striped a drive and was positioned to seize control of the tournament.
Merrick, though, caught a huge break when he found a clear opening between the trees to the green. He worked his ball through and ended up with a par, the same score as Jacobson.
"That break on 17, it's just amazing," Merrick said. "It's just one of those things that you need to win a tournament sometimes. And you know I got really lucky."
Merrick also appeared to be in trouble on the final hole of regulation, where he pushed his drive into the right rough as Jacobson's tee shot lay perfectly in the fairway.
Merrick, though, worked a low three-iron to get out of trouble and saved par.
"I was just trying to get something up there right of the flag and it came out perfectly," he said of his second shot.
Jacobson ended up with a bogey five on the hole.
Merrick, while attending UCLA, played Riviera once or twice a month — although he hasn't exactly owned the place.
In five previous professional appearances at the Northern Trust, he missed the cut three times with two other finishes of T-54 and T-64.
In 14 previous rounds, he was under par only three times. This week he shot three rounds in the 60s.
Merrick said the key was staying patient and finally giving in to Riviera, especially at No. 10.
He used to hit driver on the hole because it looked so short and easy, but Sunday used a three-iron twice on his way to birdie-par.
They say golf life begins at 30, right?
"It's hard to win a golf tournament out here unless you're Tiger Woods or Phil Mickelson," Merrick said. "They win all the time."
There's nothing, though, like the first time.
Merrick: "I'm just going to cherish this."