Phil Mickelson's legendary 66 on Sunday to win The Open Championship is No. 2 golf story of 2013

When Phil Mickelson stepped onto the 13th tee at Muirfield on Sunday at The Open, he appeared to be six holes away from a respectable finish and a long flight back to California. Instead, he proceeded to author what is likely the best six-hole stretch of his career.

He was 1-over for the tournament at the time, three strokes off the lead. Mickelson had managed to avoid disaster up to that point and remain on the fringe of contention. Still, he was an afterthought. In order to become a serious contender he'd need to dominate the hardest stretch of the course, something he failed to do during the first three rounds. Mickelson's game isn't suited for success on a links course, especially one playing as brutally hard as Muirfield was during the 2013 Open Championship.

Counting down 2013's top 25 golf stories

• No. 25: Rory moves to Nike, misery follows • No. 24: Ko wins again, 16-year old turns pro • No. 23: Stenson dominates both tour playoffs• No. 22: Snow! Floods! Wind! Lightning! • No. 21: Guan steals show at Masters • No. 20: Spieth makes history, arrives as game's next great • No. 19: Tiger goes majorless • No. 18: Woods threatens 59 at Firestone • No. 17: Vijay PED drama leads to lawsuit • No. 16: Phil's cruel lip-out prevents historic 59 • No. 15: Park wins 3 straight majors • No. 14: Tiger hits a new low at a major • No. 13: Streakers, squirrels, and dorky high-5s at the Presidents Cup • No. 12: Furyk becomes 6th ever to shoot 59• No. 11: Heartbreak at Merion for Mickelson• No. 10: Tiger retakes No. 1 after 2.5 years away• No. 9: After months of wrangling, anchors away• No. 8: Tiger's rules drama (4x) flunks Chamblee's test• No. 7: The Duf breaks out• No. 6: Rose's laser wins the U.S. Open• No. 5: Cabrera, Scott and the most dramatic 5 minutes of the year• No. 4: Fight! Sergio takes on Tiger • No. 4: Scott snaps the Aussie curse at Augusta

The stretch from No. 13 to No. 18 featured six of the eight hardest holes on the course. He played that loop at 4-over during the first three rounds. Mickelson, however, was playing well, 1-under on his round. If he could somehow manage to play the brutal closing stretch at even par he might be in the playoff discussion. As it turns out, he didn't need a playoff, because he blew away the field.

Mickelson's run to the Claret Jug began on No. 13. He hit an absolutely beautiful tee shot on the 193-yard Par-3 hole, setting up an easy birdie. He was back to even par for the first time since his 16th hole in the second round. A decent approach left him with a 30-foot birdie try on No. 14, possibly the hardest green on the course. Mickelson's putting was lights out that week, possibly due to the "secret" he'd found to cure his putting woes. Whatever he did, it worked. He rolled in the long birdie try and just like that he was in the red.

His birdies down the stretch garnered the attention, but it may have been the par saves at the 15th and 16th that won him the tournament. Mickelson may have won the U.S. Open at Merion if not for a couple of lipped par-saving putts. On the closing stretch at Muirfield, both par-savers found the bottom of the cup.

That brought him to No. 17, which may go down as the signature hole of Mickelson's career. In the week leading up to the British Open, much was made about Mickelson's decision to not carry a driver. He instead opted to take his Callaway 3-wood off the tee and carry five wedges. While the move was designed to give him more accuracy off the tee and help him on approach shots, it limited his ability to attack the long Par-5s. In order to reach the 578-yard Par-5 17th hole, Mickelson would have to hit two perfect 3-woods.

He did exactly that.

Mickelson drilled a 3-wood off the tee, setting him up with a second shot from the middle of the fairway. The course was playing firm, allowing for plenty of rollout, but Mickelson still needed to hit his second shot perfectly to have a chance. He hit it pure, right on line and added a little vocal encouragement to help.

"Go baby! Come on!"

The ball landed in a perfect spot and took a huge bounce toward the green. It rolled down a slope and settled on the front edge, leaving him an eagle putt. With the leaders faltering, Mickelson was now in position to take the lead outright. He missed the eagle, but made the tap-in birdie putt to move to 2-under.

At that point, Mickelson was in great position to win. He wasn't done yet, however, and proceeded to put the cherry on top of the round of his career. All he needed to do was avoid trouble on No. 18. That can be easier said than done, but not for Mickelson on this day. His approach shot all but sealed the victory.

And then the exclamation point.

While seemingly every other player on the course was caught up in an avalanche of bogeys and miscues, Mickelson made it look easy. He dominated the toughest stretch on one of most difficult British Open courses in history.

"It was the biggest challenge of my career," Mickelson said after the round. "It was always the tournament where I had the hardest time playing my best. And yet, I've played probably the best round of my career here in the final round of the British Open."

Colin Montgomerie took it a step further, calling it one of the best rounds in the 142-year history of The Open. While its place in history remains up for debate, it's hard to imagine any player, in any generation, playing that final stretch better than Mickelson did that day. He was nearly flawless in all facets. His tee shots found the middle of the fairways. He drilled approach shots into birdie range despite brutal conditions. Once he got on the green, he putted like the best in the world.

Mickelson plugged away through the first 66 holes only to truly save the best for last. From there, the only thing left to do was celebrate.

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