British Open Results 2013: Dark Horses in the Hunt for Title at Muirfield

Three rounds in, it's safe to say this has been a very unpredictable edition of the Open Championship.

There are just three golfers playing under-par, leads have changed hands regularly and still there's one very important round to be played.

That's why today's Round 4 will be one of the most entertaining days of golf in recent memory.

In general, this PGA season has seen two golfers win their first-ever majors at the Masters and U.S. Open, and if the final round of the British Open goes anything like the first three, that trend will continue tomorrow afternoon.

Great Britain's own Lee Westwood enters Sunday with a two-shot lead on Tiger Woods and Hunter Mahan, and unfortunately for his challengers, the 40-year-old has only gotten better as the tournament's worn on.

But there are others in the hunt, so heading into the final round, here's a look at some of the less-heralded golfers still in contention for the third major of the season.

Ryan Moore

American Ryan Moore currently sits tied for fifth at plus-one, but the 30-year-old's consistency has been a positive indication of things to come, as he's shot within a stroke of par in each of the first three rounds.

Making up this much ground on Westwood will be difficult, especially given how little experience Moore has in contending for major titles on a grand stage such as this, but if he can manage to stay on par on Sunday, he'll be in the mix. 

Henrik Stenson

This shouldn't be a complete surprise, because Stenson's been sniffing around the top of the leaderboard at this tournament before, but given that he's still searching for his first major, he's surely not disappointed with his play thus far.

As a player who tied for third place at the Open Championship in both 2008 and 2010, Stenson has proven that he belongs among the world's best, especially in the United Kingdom.

In fact, had Stenson continued to play the way he did during the first two rounds, he'd be heading into Sunday just three shots off the leader, but his plus-three performance on Saturday made things significantly more difficult for the 37-year-old Swede.

Zach Johnson

After leading the tournament through Round 1, Zach Johnson stumbled during the following two days of play, and now sits tied with Stenson and Moore, four shots back of Westwood.

It's unfortunate for the former Masters champion, because after shooting a minus-five on Thursday, Johnson has failed to play even-par golf since, and dug himself a sizable hole heading into Sunday.

Though Johnson still has almost as good of a shot at catching the front-runners, it'll take an effort similar to the one he served up on Thursday in order to launch himself back into legitimate contention.