British Open 2015: Leaderboard Scores and Highlights from Friday

The 2015 Open Championship's second round at St. Andrews in Scotland won't conclude until Saturday due to weather delays, but the rain didn't stop Dustin Johnson from retaining his lead.

Falling just short at the U.S. Open doesn't seem to have damaged the 31-year-old American's psyche, as he is three under through 13 holes in the second round and 10 under overall with a one-stroke lead over Danny Willett. Meanwhile, Masters and U.S. Open champion Jordan Spieth is five shots behind in a tie for 15th place, although he is also only through 13 holes.

Here is a rundown of the current leaderboard with more comprehensive results available at PGATour.com:

Johnson's tournament got off to a great start in Thursday's first round, as he shot a seven-under 65 to pace the field. DJ was particularly happy with that performance since he knew what laid ahead in terms of the course conditions, according to Ben Dirs of BBC Sport.

"Everyone knows the weather is going to get difficult, so it was important to get off to a good start and try to get as many birdies as you can," Johnson said.

His analysis was accurate, as a three-hour rain delay wreaked havoc on the Old Course on Friday. It didn't negatively impact his game, though, as he maintained his position and fought off strong rounds from his challengers.

His front nine was especially impressive, as he birdied three holes and didn't post a single bogey. His length off the tee was a huge reason for his success, and ESPN's Dave Flemming couldn't help but marvel at it:

ESPN's Jason Sobel was hugely impressed with the cleanliness of Johnson's game through one-and-a-half rounds at St. Andrews as well:

Johnson's assault on the Old Course carried over to the 10th hole, where he posted his fourth birdie of the day. his performance so far elicited a bold prediction from Stephanie Wei of SI Golf:

Johnson also drew praise from Sobel for his ability to make things look easy:

DJ's incredible run without a bogey came to an end on the 11th hole, when he posted a four on the par-three hole. But that didn't detract much from his excellent round.

Johnson was far from the only one who turned in a strong showing Friday, though. Willett had the clubhouse lead at nine under when his round concluded, and although he was eventually surpassed by Johnson, he is very much in the hunt for his first career major title.

Willett shot a three-under 69 in the second round and was thrilled about the position he managed to put himself in:

Considering Willett's previous lack of success in majors, his continued strong play was fairly unexpected. ESPN Stats & Info provided some evidence of just how remarkable Willett's performance has been when compared to his past major results:

One of the day's best rounds came courtesy of 2013 Masters winner Adam Scott, who carded a five-under 67 to move to seven under overall.

The Aussie's play has been inconsistent over the past couple of years, but as pointed out by Kelly Tilghman of Golf Channel, his reunion with caddie Steve Williams seems to be paying dividends:

Johnson's playing partners had differing days. Spieth had his ups and downs, while Hideki Matsuyama was among the best golfers on the course.

Spieth is at even par through 13 holes in the second round and sits five under for the tourney, which means he will have some work to do to position himself for a run at his third consecutive major championship. He has proved to be capable of coming from behind to win, but he'll need to turn up his level of play in a big way.

Matsuyama, on the other hand, entered the second round at even par, but he played some unbelievable golf Friday. Through the first 10 holes, he birdied seven of them and parred the other three. ESPN's Trey Wingo broke down the Japanese youngster's remarkable short game:

His round lost a bit of luster with bogeys on the 11th and 12th holes, but going five under through 13 holes has him back in contention.

After shooting a four-over 76, Tiger Woods needed a big day to avoid missing the cut. He still has seven holes to play in the second round, but at one over on the round and five over for the tournament, the likelihood of reaching the even-par cut line is very low.

Many have blamed Tiger's struggles on a transition to a new swing, but his former swing coach, Hank Haney, isn't buying it:

While most, including Tiger, decided to pack it in for the day in what was nearly pitch-black darkness, Tom Watson and playing partners Ernie Els and Brandt Snedeker decided to finish out the round.

Watson, who won The Open Championship five times, missed the cut in his final British Open at the age of 65, but Tilghman believes his final round reached a fitting conclusion:

"

Tom Watson's final round at St Andrews is much like his career. Squeezing every last possible minute of daylight before he's done.

— Kelly Tilghman (@KellyTilghmanGC) July 17, 2015"

The crowd had thinned out considerably by the time Watson approached the 18th green, but it made for a unique moment, as seen in this photo courtesy of BBC Sport:

Watson is one of the greatest golfers in the history of The Open Championship, and while he won't figure into the 2015 title run, the conclusion to this year's British Open is shaping up to be an exciting one.

Johnson remains the man to beat with part of the second round left to be played, but his past inability to close out major leads makes him quite vulnerable at the top of the leaderboard.

With past major champions like Scott, Zach Johnson and Louis Oosthuizen lurking a few strokes behind and multi-time near-major champ Jason Day just a couple of shots back, there is plenty left to be decided.

Many eyes will be on Spieth as well since his pursuit of the 2015 Grand Slam continues. He has five shots to make up in a little more than two rounds. Golf fans certainly aren't ready to count him out, and Johnson surely won't write him off either.

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