British Open 2013: Phil Mickelson and Biggest Threats to Leaders on Day 4

Three days into the 2013 British Open, names like Tiger Woods, Adam Scott and Zach Johnson are sitting close to the top of the leaderboard. Just because those golfers are at the top heading into the last day, however, doesn't mean they will stay there.

There are more than a few names who are just as hungry for this year's British Open championship and are not far behind. Here are some of the biggest names the leaders must keep an eye on during Day 4.

Phil Mickelson

Mickelson has never won the British Open and sits five shots out of the lead heading into Day 4. That being said, Lefty shouldn't be counted out of finding his way into first place.

He finished Day 3 with a one-over par 72 with two birdies to his credit. Not a bad round of play for the same golfer who recently won the Scottish Open. While the British and Scottish Open are two different tournaments, Mickelson has tasted first place quite recently.

Given his 19 past failures at winning this tournament, it's easy to write off the three-time Masters winner. Do not, however, write off Mickelson on Day 4 given his recent success and play in this tournament.

Dustin Johnson

Like Mickelson, Johnson has never won the British Open, but he did finish second in the 2011 edition of the tournament. On Day 3 of this year's tournament, he shot a five-over par 76 with three bogeys, a double-bogey and birdie. 

While that stat line is surely not what Johnson was hoping for heading into that day on the green, he sits tied for 11th place in the current standings.

He doesn't have any major tournament victories to his name, but he still has a chance to make noise in this one. Johnson will need to be nothing short of phenomenal on Day 4 to make up for his mediocre performance in the previous round.

If he does rally back, Johnson could crack the top three or five by the end of the tournament.

Sergio Garcia

Tied with Johnson and five others in 11th place, Garcia is a name that could move up the board early on Day 4 as well. While he doesn't have a ton of huge wins to his name since 2008, Garcia is close enough to the top of the leaderboard to make a run.

On a day where other top names struggled, Garcia shot a three-under par 68 on Day 3 with three birdies and one bogey. Over the first three days of this tournament, Garcia has gone from shooting four-over and two-over par to three-under.

The native Spaniard has been trending up toward the top for the past few days now. Garcia has a legitimate chance to come close to or match his 2007 second-place finish here.