The extended PGA Tour hiatus because of the COVID-19 pandemic means this week we’re without one of the more exciting events on the schedule.

There won’t be any jaw-dropping upsets or dramatic comebacks this week at the WGC-Dell Match Play Championship, which is one of the more unpredictable tournaments contested each year. But that doesn’t mean we can’t look back on a few memorable – and improbable – moments.

From unexpected singular match results to dramatic runs through the bracket, here's a look back on 10 of the biggest upsets in the 20-year history of the event:

Nick O’Hern tops Tiger (2005, 2007)

Tiger Woods may be the greatest player of his generation, but he had an Achilles’ heel when it came to this event: specifically, one lanky, left-handed Aussie. O’Hern never won on the PGA Tour, but that didn’t stop him from surviving a showdown with Woods at the height of his powers – not once, but twice.

The first upset came in 2005, when the tournament was held at La Costa and the two met in the second round. O’Hern barely survived his No. 8 vs. No. 9 opener against Charles Howell III, which earned him a date with the two-time defending champ. Woods hadn’t lost in this event in three years, but he was no match for O’Hern, who putted his way to a 3-and-1 victory. He’d eventually lose to Ian Poulter in the quarterfinals.

Two years later at Dove Mountain, the two met again with Woods riding a seven-tournament winning streak on the PGA Tour. He cruised through his first two matches, but again couldn’t keep pace with O’Hern, who outlasted Woods with a par on the 20^th hole.

“To beat him once was an amazing thrill, and I’m sure he wanted to even the score today,” O’Hern told reporters. “It’s something to tell the grandkids, I guess.”

Peter O’Malley stuns Woods (2002)

Before O’Hern got his claws into Woods, another Aussie showed it was possible by pulling off the biggest upset to date in tournament history. O’Malley was a 36-year-old journeyman with three European Tour wins to his credit but not much U.S. success. He was the lowest-ranked player in the field, No. 64 overall, and got in only when Jose Coceres withdrew because of injury.

Woods was the reigning Masters champ, but he struggled on the greens against O’Malley at La Costa and didn’t record a single birdie until the 16^th hole. By then it was too late, as O’Malley closed out the match, 2 and 1, with a 20-foot putt on the next hole.

“I had a no-lose situation, really,” O’Malley said. “No one expected me to win, so I can just go out there and play my game and if I win, well, it’s great. And if I don’t, it doesn’t really matter.”

It was the first time the tournament’s lowest-ranked seed won a match. O’Malley went on to lose to Nick Price in the second round and never played in the event again.

Darren Clarke takes down Tiger (2000)

In February 2000, Woods was still a couple months removed from starting the Tiger Slam. But he was already playing some of the best golf of his career, and Clarke’s run to the semifinals appeared destined to end when he, as a 5 seed, was left standing against three No. 1 seeds: Woods, Davis Love III and David Duval.

But the Ulsterman dispatched Duval in the semis to set the stage for a memorable finale. Clarke not only beat Woods in the 36-hole match, earning his first Tour title in the process, he did so in resounding fashion. The match ended, 4 and 3, after Clarke poured in 12 birdies across 33 holes and missed just one green over his final 17 holes. Even Woods, near his all-time peak, couldn’t keep up.

“Darren just flat outplayed me,” Woods said.

Clarke only won three times on the PGA Tour, but all were significant: he added another WGC title at Firestone in 2003 and lifted the claret jug in 2011.

Hunter Mahan stops Rory McIlroy’s run to No. 1 (2012)

Clarke’s wasn’t the only memorable upset in the tournament’s final match. By the 2012 edition, the final had been trimmed to 18 holes, and it seemed like a fait accompli when 6-seed Hunter Mahan went up against top seed Rory McIlroy.

McIlroy was the reigning U.S. Open champ, and with a victory over Mahan he would reach world No. 1 for the first time. Instead it was Mahan’s day to shine, as he won three straight holes on the front nine and never looked back. He won the match, 2 and 1, for the fourth of his six career victories.

“Deep down, you wanted to postpone that crowning of the No. 1 player in the world for Rory,” Mahan said. “He’ll get there. I mean, he’s phenomenal. He’s really talented. He’ll be No. 1 eventually.”

Mahan’s prediction proved accurate. McIlroy won the Honda Classic in his next start to reach No. 1 for the first time, a spot he happens to currently hold.

Shane Lowry knocks off friend Rory McIlroy (2013)

The relationship between Lowry and McIlroy stretched back to their days playing junior golf in Ireland, and the two met again in the opening round in 2013. While they may seem an even match currently, with Lowry in possession of the claret jug, seven years ago he had barely qualified for the 64-man field and was struggling with his game.

But 2013 was a weird year for this event – on top of Dove Mountain being unexpectedly blanketed with snow, two of the top seeds lost in the opening round. That included McIlroy, the tournament’s No. 1 overall seed.

McIlroy and Lowry had even eaten dinner together the night before their match at a local restaurant, but once they hit the course it was the world No. 66 who edged his buddy with a par on the 18^th hole.

“It’s definitely a day I’m going to remember,” Lowry said. “I’m sure, after a few weeks or a couple months, I will slag Rory over it. But at the end of the day, it’s only the first round.”

Lowry went on to lose the next day to another good friend, Graeme McDowell.

Kevin Sutherland wins as a 16 seed (2002)

Which Match Play overall winner is most surprising? Kevin Sutherland, by a mile. He barely qualified, ranked 62^nd among a 64-man field at La Costa, and seemed headed for a quick exit as a 16 seed up against reigning Open champ David Duval in the opening round.

But Sutherland won that match, escaping from a 1-down deficit with two holes to go. Then he beat Paul McGinley, Jim Furyk and reigning PGA champ David Toms to make the semifinals. There he beat Brad Faxon, and in the most unpredictable final ever, he beat 12-seed Scott McCarron, 1-up, for the $1 million prize.

“I could have easily lost to David in the first round and it wouldn’t have been a very good week,” Sutherland said. “But as it turned out, the victory really opened quite a few doors for me.”

The whirlwind week changed Sutherland’s perception on Tour, but it turned out to be the only victory of his PGA Tour career. He went on to find success on PGA Tour Champions, shooting a 59 and winning a season-long Schwab Cup title in 2017.

Steve Stricker comes out of nowhere Down Under (2001)

The 2001 edition of the event remains the most unique: it was the only one held outside the U.S., played at Metropolitan Golf Club in Melbourne, Australia. And it was held in early January rather than late February, a scheduling quirk that contributed to four of the world’s top five players sitting it out.

But Stricker made the trek to Oz, where he started as a 14 seed against No. 3 seed Padraig Harrington. The American was ranked 91^st in the world, hadn’t played a Tour event since September and was five years removed from his most recent win.

But he beat Harrington, then Scott Verplank and No. 2 seed Justin Leonard. In the quarterfinals he faced another upstart, No. 16 seed O’Hern, but beat the Aussie on his home turf before taking out Toru Taniguchi. That left only Sweden’s Pierre Fulke in his way, and Stricker took the 36-hole final with a 2-and-1 victory.

Stricker would have missed out on a spot in the field by a wide margin had the top names played, but instead he earned a breakthrough win after trailing for only nine holes all week.

“They all had the opportunity to commit and come over, and they didn’t,” Stricker said. “That’s all I care about. It’s a big win, my biggest win, and it gets me going in the right direction.”

Stricker would go on to lose his Tour card in 2004, but would win again in 2007 to spark a late career resurgence.

Steve Pate erupts in opening year (1999)

Known as the "Volcano” for his explosive on-course personality, Pate barely qualified the first time this event was played as a WGC back in 1999, ranked No. 61 out of 64 players. That standing earned him an opening match against Davis Love III, who was a runner-up at Riviera just one week prior.

But Pate pulled off the upset, presenting an example of how unpredictable the single-elimination format can be, and he didn’t stop there. He beat Brandt Jobe, Fred Couples and Eduardo Romero to head to the semifinals as the highest possible seed on his side of the bracket.

There he met Jeff Maggert, and Pate appeared well on his way after building a 3-up lead through 11 holes. But Maggert stormed back, beating Pate en route to a title the next day. Pate ended up fourth, also losing the consolation match to John Huston, but his run through the bracket was a big reason why he was chosen as a captain’s pick by Ben Crenshaw a few months later to round out the 1999 U.S. Ryder Cup squad.

Dubuisson takes on nature (2014)

Victor Dubuisson was a largely unheralded figure in the golf world until he took on an elite field – and Mother Nature – in a stirring performance.

The Frenchman was the 7 seed in the Sam Snead bracket, and early wins over Kevin Streelman and Peter Hanson didn’t draw much attention. But when he knocked out Bubba Watson and Graeme McDowell to reach the semifinals, people started to notice.

The ’14 bracket had some quirks to it: Ernie Els toppled wunderkind Jordan Spieth in a semifinal run that marked one of his few post-Lytham highlights, and Rickie Fowler made the semis (as a 14 seed!). But there was no bigger surprise than Dubuisson, who flashed his short game magic across Dove Mountain to advance to the final against Jason Day.

Dubuisson was 3 down with six holes to go and 2 down with three to play before storming back, burying putts on Nos. 17 and 18 to force overtime. On the first extra hole his approach ended up in a cactus but he somehow hacked it out onto the green to save par, only to repeat the heroics from the junk on the very next hole to keep his hopes alive. Day eventually won on the 23^rd hole, but Dubuisson’s improbable escapes were the main takeaway from a memorable finale.

He went on to play in the Ryder Cup a few months later, but he hasn’t won in Europe since 2015 and hasn’t factored in the U.S. since his runner-up showing in Arizona.

Bjerregaard upsets Tiger (2019)

The tournament’s format switched in 2015, featuring group play along with a single-elimination bracket. Last year, Denmark’s Lucas Bjerregaard was fortunate just to escape the group portion, as the lowest seed in a four-man group that also included Justin Thomas, Keegan Bradley and Matt Wallace.

Bjerregaard followed with another upset over Henrik Stenson to earn a quarterfinals match against Tiger Woods. Woods was playing well, and earlier in the morning had beaten Rory McIlroy in the most anticipated match of the week. But the Dane proved to be too much, as Woods lipped out a 5-foot par putt on No. 18 that would have extended the match.

“Yeah, I dreamt about it. I didn’t think it was ever going to come true,” Bjerregaard said. “But I’ve definitely seen myself on the practice putting green when I was 10 years old making a putt to beat him or in a major or something like that. I won’t lie.”

Bjerregaard lost to Matt Kuchar in the semifinals, ultimately finished fourth and hasn’t done much of note in the 12 months since. Woods, as you may have heard, went on to win the Masters two months later.