CHARLOTTE, N.C. — Surprise, surprise, surprise.

On Sunday, six days after Derek Ernst received a call that he was in the Wells Fargo Championship as the fourth alternate, the 22-year-old rookie found himself one shot out of the lead and 192 yards away from the flag on the 18th hole, the toughest at Quail Hollow in the cold, wind and rain of a grueling final round.

Ernst choked up on a 6-iron and hit a draw that landed 4 feet from the hole for one of only four birdies on the closing hole Sunday.

“I was trying to hit it as close as I possibly could,” he said.

The birdie gave him a 2-under 70 and tied him with David Lynn of England, who also had a 70. And it turned out to be no fluke. Returning to the 18th in the playoff, as the rain started coming out harder, Ernst hit a 3-iron to about 15 feet left of the flag that set up his stunning victory.

Phil Mickelson didn’t get a chance to join them. He had a one-shot lead with three holes to play until making back-to-back bogeys, missing putts of 6 feet and 10 feet. His 20-foot birdie putt on the 18th narrowly missed, and Mickelson closed with a 73.

“I felt like I was in control, and I let it slip away there the last few holes, so it was disappointing,” Mickelson said.

So ended a strange week at Quail Hollow. The greens were shockingly bad due to weather and agronomical issues, which led to several players dropping out. The sun never really came out all week, and the wind chill Sunday morning made it hard to believe it was the first weekend in May. It felt like February at Pebble Beach.

Turns out there was one final surprise.

Ernst was playing only his ninth PGA Tour event. He was No. 1,207 in the world ranking. He was in a car headed to Athens, Ga., to play a Web.com Tour event when he got the phone call that there was a tee time for him at Quail Hollow.

“This feeling is unbelievable right now,” said Ernst, who wasn’t sure where he was going at the start of the week and can’t believe where he’s going now.

For starters, the victory at Quail Hollow gets him into The Players Championship next week. He qualifies for two World Golf Championships, the PGA Championship, the Tournament of Champions next year at Kapalua and the Masters next April.

Before coming to Charlotte, the rookie swapped out rental cars in Georgia so he wouldn’t have to pay the $1,000 fee for dropping the car in another location. Along with a two-year exemption on tour, the win earned him just over $1.2 million.

Lynn played the final three holes, known as the “Green Mile,” in a combined 4-under par for the week without a single bogey. He chipped in from 70 feet for birdie on the 16th, to go along with a 55-foot chip-in on the 17th on Saturday and a 40-foot chip-in for birdie on the 18th on Friday.

But he picked a bad time for his lone mistake on that stretch.

His tee shot in the playoff was headed for the creek on the left side, though it stayed up in shaggy grass on the bank, the ball well above his feet. Lynn was thinking about laying up until he saw Ernst fire his 3-iron into birdie range. He tried to match him with a hybrid, but the ball didn’t turn over enough and caught the bunker. He blasted out of the wet sand and over the green and chipped to 5 feet. He had that left for bogey, and never had to putt.

“I’ve not been particularly driving it well, so took that tee shot down in the playoff and obviously found a bit of a crooked spot and then didn’t play a great bunker shot either,” Lynn said.

Early in the final round, the leaderboard featured Mickelson and Nick Watney at the top, with McIlroy and Lee Westwood right behind.

When it was over, the winner was Ernst, who grew up in the central valley of California and has cloudy vision out of his right eye from a freak accident as a kid, when a piece of plastic pipe sliced into his eyeball and required 10 stitches.

“I’ve never heard of him,” Lynn said. “He’s a nice player. He said he was 180th on the FedEx Cup list when we were chatting on the way around. He played super. I mean, he could have won it quite easily in regular play. He played the finish really solid, and then he hit two really solid shots in the playoff. So every credit to him. Well done.”

Robert Karlsson, the Swede who now lives in Charlotte, needed a birdie on the last hole to get into the playoff but made bogey for a 72. That left him in a tie for fourth with Westwood, who was tied for the lead until back-to-back bogeys early on the back nine.

McIlroy was one shot behind when he made a double bogey on the 12th hole. He played that hole in 4-over for the week. He had a 73 and tied for 10th.

None of the contenders was more disappointed than Mickelson. He badly wanted to add his name to the list of winners at Quail Hollow, which in its first 10 years already included six major champions. But for the second straight day, the final stretch of holes did him in.

Mickelson took a one-shot lead with a chip that settled inches away for a tap-in birdie on the 14th, and he was poised to widen his lead on the par-5 15th. His second shot came up just short and into the bunker, but Mickelson could only blast that out to 12 feet and he left the birdie putt short. That proved costly.

He missed a 6-foot par putt on the 16th — at the point, Ernst and Lynn had finished at 8-under 280 — and three-putted from 65 feet away off the green on the 17th for bogey.

“I’m pretty bummed out,” Mickelson said. “I thought that this was one I had in control. If I could have gotten that bunker shot up-and-down on 15, I would have had a two-shot lead heading into those last three holes, which I know are difficult holes, so it would have been nice to have that.

“There is just no excuse,” he said. “It wasn’t easy, but it wasn’t anything out of the ordinary or difficult. I should have made par.”

Even though hardly anyone was paying attention to Ernst — not with so many big names in the hunt over the last two hours — he might have played the best golf.

Ernst hit a beautiful wedge from about 100 yards into 4 feet to escape with par on the 12th. He missed birdie putts from 5 feet on the 14th after nearly driving the green, and he missed another birdie putt from 6 feet on the 16th. But he made the birdie that mattered, on the 18th in regulation, to set up his big win.

 Final Round leaderboard: Derek Ernst 67-71-72-70—280 (-8); David Lynn 71-68-71-70—280 (-8); Phil Mickelson 68-67-73-73—281 (-7).

Derek Ernst

–Joins Jim Furyk (2003) as the only first-round leaders/co-leaders of this event who held on for the win.

— Moves to No. 32 in the FedExCup standings with 528 points.

–Is the second rookie and the youngest player (22 years, 11 months, 19 days) to win on Tour this season ahead of Russell Henley (Sony Open in Hawaii at age 23 years, 9 months 1 day).

–This was Ernst’s first start in the Wells Fargo Championship. He got a spot in the field off the alternate list on Monday when Freddie Jacobson withdrew.

— With the win, Ernst plays his way into THE PLAYERS Championship this week.

— Played the “Green Mile” (Nos. 16-18) at 2-under for the week.

— A rookie on Tour this season, Ernst played in just his eighth event of the season this week. His only two previous made cuts came in his first start of the year at the Sony Open in Hawaii (T59) and last week at the Zurich Classic of New Orleans (T47).

–Records his first top-25 finish on Tour in nine career starts. His only start prior to this year on TOUR was at the 2012 Frys.com Open (T41).

— Ernst earned his way on Tour this season after finishing T17 at the 2012 PGA Tour Qualifying Tournament. Ernst is one of four players who successfully navigated all four stages (pre-qualifying, first stage and second stage) to earn a spot on Tour.

David Lynn

— Made his 16^th career start on the PGA Tour and first in the Wells Fargo Championship this week.

— His two previous top-10 finishes on Tour came at the 2013 Honda Classic (T4) and the 2012 PGA Championship (2^nd).

–Is playing his first season as a PGA Tour member after finishing in the top-125 on the 2012 PGA Tour non-member money list.

— Lynn’s only win on the European Tour was the 2004 KLM Open.

Phil Mickelson

–Has played 31 of 40 competitive rounds at Quail Hollow at par or better.

–Holds the Wells Fargo Championship record for the most top ten finishes, with seven in 10 appearances. Along with his solo second in 2010, he finished T5 in 2004, T7 in 2005, T3 in 2007, T5 in 2009, T9 in 2011, 3^rd in 2013.

— Has played No. 17 at Quail Hollow Club 40 times and is 14-over-par on the hole. He has only birdied the hole three times (R4/2007, R2/2010 and R4/2012). He made a bogey in the final round.

— Of the stroke-play events on Tour in which Mickelson has competed more than 10 times, the BMW Championship (15 starts), WGC-Bridgestone Invitational (14 starts), the Memorial (13 starts), The Barclays (11 starts) and the Wells Fargo Championship (10) are the only ones to have never surrendered him victory.

— Made his 15^th start on the PGA Tour in the state of North Carolina this week, where he remains in search of his first win. In addition to 10 starts at Quail Hollow, he played the Wyndham Championship at Forrest Oaks CC in Greensboro in 1993 (T50), 1997 (T9) and 1998 (T6). In the U.S. Open at Pinehurst, he finished runner-up in 1999 and T33 in 2005.