PORTRUSH, Northern Ireland -- The Open is returning to Irish soil for the first time in 68 years this week, with golf's best players gathering at Royal Portrush Golf Club for the year's final major championship.

The 148th edition of The Open is being called the greatest sporting event in Northern Ireland's history. Tickets for all four days of the tournament sold out for the first time in history and more than 190,000 fans are expected to attend.

Here's everything you need to know about The Open:

About the course

David Cannon/R&A/R&A/Getty Images

Royal Portrush Golf Club, founded in 1888 on the northern coast of Northern Ireland, is the only club outside of England and Scotland to host The Open. It was the site of the 80th Open Championship in 1951, when Max Faulkner won the Claret Jug.

In 2014, the R&A announced that Royal Portrush was returning to The Open rota. Starting in November 2015, golf architects Mackenzie & Ebert spent 18 months redesigning and lengthening the Dunluce links course to accommodate modern players.

They designed five new greens, eight new tee boxes, 10 new bunkers and two new holes -- Nos. 7 and 8, on land that was originally part of the adjoining Valley Course. What was originally the seventh hole on Dunluce is now the ninth, followed by the same Nos. 10-16 holes that were part of Harry Colt's design in 1929.

The original 17th and 18th holes on Dunluce, which were regarded as rather ordinary for finishing holes in a major championship, were removed to accommodate space for tents and other buildings needed for The Open.

Holes to know

It took 68 years for The Open to return to Northern Ireland and Royal Portrush. Liam McBurney/PA Images/Getty Images

Two of the most dramatic holes on the Dunluce Course are located near the Atlantic Ocean shore.

The par-4, 374-yard fifth, called "White Rocks," is widely regarded as the course's signature hole. It is a dogleg hole, from left to right, with an elevated tee shot toward the Atlantic Ocean. It requires a daring tee shot over a wide expanse of thick rough, which is even more treacherous when the wind is howling. The green sits perched on the very edge of the course, with White Rocks Beach (and out of bounds) about 50 feet below.

The 236-yard, par-3 16th (formerly the 14th) is known as "Calamity Corner" and requires an uphill tee shot over a yawning void. Making matters worse, there is a deep chasm, covered in nasty rough, to the right of the small green.

The two new holes are considered among the track's best. The par-5, 592-yard seventh, known as "Curran Point," might challenge even the longest hitters. The elevated tee box is exposed to the wind, which will make it more difficult hitting to a narrow fairway protected by a maze of dunes. Players also will have to avoid a massive bunker on the right side, a replica of "Big Nellie," the celebrated bunker on the original 17th hole.

The new eighth hole, "Dunluce," is a dogleg-left, 434-yard par 4 that requires players to drive over dunes to a narrow fairway. Its green has a massive false front, which will certainly claim its share of victims this week.

The favorites

Brooks Koepka

At this point, it almost seems like a bigger story if Koepka doesn't win a major. He has won four of the past 10 majors and finished runner-up twice. And how's this for an advantage: His caddie, Ricky Elliott, is a native of Portrush and played the old Dunluce course as a junior. That can only help Koepka.

Rory McIlroy

Yeah, he hasn't won a major in nearly five years and wasn't in contention at Augusta or Bethpage Black and didn't finish well at Pebble Beach. But he still has two wins and 11 top-10s in 14 PGA Tour starts this season. When you combine McIlory's talent and local knowledge, the native son might be tough to beat with the home crowd behind him.

Francesco Molinari

Molinari stared down Tiger Woods in the final round of The Open in 2018 at Carnoustie and won by two shots to become the first Italian to win a major. But he hasn't played very well since his collapse on Sunday at Augusta this year, finishing tied for 48th at the PGA Championship and tied for 16th at the U.S. Open.

Dustin Johnson

The No. 2 player in the world has been at his best this season in the majors, finishing tied for second at the Masters and solo second at the PGA Championship. One cause for concern: Johnson was tied for 35th at Pebble Beach, where wind was also a factor. DJ missed the cut at Carnoustie last year and hasn't played well in this event during his career, other than a tie for second in 2011.

Justin Rose

The former World No. 1 missed the cut at the Masters and tied for 29th at the PGA Championship. But he was in contention at the U.S. Open until shooting 74 on Sunday and finishing tied for third. Rose is the most improved putter on Tour, and that might give him a chance to become the first Englishman to win the Open since Nick Faldo in 1992.

Jon Rahm

The Spaniard just won the Irish Open for the second time in three years and has played well in two of the three previous majors this season, finishing tied for ninth at the Masters and tied for third at the U.S. Open. He hasn't finished higher than a tie for 44th in three appearances at The Open.

Tiger Watch

Tiger hasn't played a competitive round since the U.S. Open. Will there be rust? Ian Johnson/Icon Sportswire/Getty Images

Tiger Woods was one of the first players out on Royal Portrush for a Sunday morning practice. Still, he has not played tournament golf in a month, since finishing tied for 21st at the U.S. Open.

Woods has made only three starts since winning the Masters in April at Augusta National for his 15th major championship. After winning a green jacket for a fifth time, he didn't play before missing the cut at Bethpage Black and hasn't played since a disappointing finish at Pebble Beach.

Still, Woods was in contention at The Open at Carnoustie last year until a forgettable start to his back nine on Sunday, when he had a double-bogey on the 11th and bogey on the 12th.

Woods spent much of the past month traveling with his family in Thailand. He has won The Open three times, most recently at Royal Liverpool in 2006.

Why isn't Matthew Wolff here?

It's a shame the rookie sensation with the funky swing won't be teeing it up at Royal Portrush this week. Wolff, the reigning NCAA Player of the Year from Oklahoma State, won the 3M Open in only his third start as a pro with a back-nine 31 and walk-off eagle on No. 18 in the final round.

While the victory secured Wolff a two-year exemption on the PGA Tour, a spot in next year's Masters and PGA Championship and a $1.152 million payday, it didn't earn him a spot in The Open Championship. This past week's John Deere Classic is among the qualifying events for The Open -- but not the 3M Open. To qualify, Wolff needs to finish in the top five and above any other players who had not yet qualified. He entered Sunday's final round in a tie for 33rd.

Salvaging the majors

Here are some players who are looking to rebound after disappointing performances in the first three majors this season:

Tommy Fleetwood

The 28-year-old hasn't won on the PGA Tour, but he was runner-up at the 2018 U.S. Open and tied for 12th at Carnoustie. He hasn't been nearly as good in majors this season, however, with a tie for 36th at Augusta, tie for 48th at the PGA Championship and tie for 65th at the U.S. Open.

Rickie Fowler

The best player to never win a major is now 0-for-39 in golf's biggest events. He grabbed a share of the early lead at Pebble Beach before imploding with a 77 on Friday. He tied for ninth at Augusta and tied for 36th at Bethpage Black. His best finish in The Open was a tie for second at Royal Liverpool in 2014.

Jordan Spieth

The three-time major winner's game remains a mess, after a tie for 65th at the U.S. Open and a missed cut at the Travelers. He was in contention at Carnoustie last year until a final-round 76, and his last victory came at The Open in 2017 at Royal Birkdale.

Justin Thomas

A wrist injury derailed JT's season after a hot start. He tied for 12th at Augusta, missed the PGA Championship because of the injury and then missed the cut at the U.S. Open. He ranks 10th in shots gained total but only 166th in shots gained putting.

Homeland heroes

Quite a few players from Northern Ireland and Ireland will be competing in The Open:

Rory McIlroy

The four-time major winner will be returning to a course where he's very comfortable and had great success. McIlroy grew up in Holywood, Northern Ireland, and he set the Dunluce course record at Royal Portrush when he was 16 with an 11-under 61 in the 2005 North of Ireland Amateur Championship.

Darren Clarke

Clarke, the 2011 Open winner at Royal St. George's, lives in Portrush and is an honorary member of the club. Clarke, 50, has missed the cut in three of the previous four Opens.

Graeme McDowell

McDowell was born in Portrush and splits his time between Orlando, Florida, and there. The 2010 U.S. Open champion qualified for The Open at his home course by finishing tied for eighth at the RBC Canadian Open in June.

Padraig Harrington

Harrington, 47, grew up in Dublin and is an honorary member at Portrush. He has won six times on the PGA Tour and 15 times on the European Tour, including The Open at Carnoustie in 2007 and Royal Birkdale in 2008.

Shane Lowry

Lowry, 32, won the Irish Open as an amateur in 2009 and has one victory on the PGA Tour -- the 2015 WGC-Bridgestone Invitational. He has three top-10s in 11 PGA Tour starts this season, including a tie for second at the Canadian Open.