Take a look at these to work out when best to take your lunch break.

12:31 Todd Hamilton (US), Justin Leonard (US), Mark Calcavecchia (US)

12:53 Paul Casey (Eng), Charl Schwartzel (SA), Kevin Na (US)

13:15 Graeme McDowell (NI), Matt Kuchar (US), Andrew Johnston (Eng)

13:26 Phil Mickelson (US), Lee Westwood (Eng), Ernie Els (SA)

14:04 Dustin Johnson (US), Martin Kaymer (Ger), Russell Knox (Sco)

14:15 Zach Johnson (US), Adam Scott (Aus), Henrik Stenson (Swe)

Image source, AP

As we say, it is not going well for Shane Lowry.

After his excellent showing at the US Open and being back on a links course, we thought the Irishman may be a threat. 

The big man is five over though, he's hit just 40% of fairways and with 21 putts through 12 holes, his putter isn't sizzling either. Five over. 

World number three Jordan Spieth is struggling in the Scottish sunshine.

A bogey at the pesky 11th leaves him at par, four shots behind the leaders.

A clean back nine so far for Spieth's playing partner Justin Rose who is on one-under while Shane Lowry has had a nightmare after the turn.

Bogey, bogey, double bogey for the Irishman.

Image source, AP

Watch this incredible tee shot from Rory McIlroy on the incredibly short par-three Postage Stamp. 

Rory McIlroy enjoys a touch of good fortune on the 11th after skewing his tee shot right. His ball lands among the spectators, but the grass is nicely trodden.

The world number four is able to find a promising position on the green with his third shot, and he sinks an easy putt for par to stay four under and keep a share of the lead.

Lee Fitzjohn: A few years back I sliced a tee shot into water and hit second one to within 3 inches. Devastated if that had gone in...

Damian Hull: 14 years old. Hole 2 of the old 5 hole Golf Course in Red City Park, Grimethorpe, Barnsley. Only owned a 4 iron....my first and only.

Danny Willett misses a putt on the 11th and that is back-to-back bogeys for the Masters champion who drops to one-under-par.

Mixed fortunes for his playing partners.

American Rickie Fowler is yet to drop a shot on two-under while world number one Jason Day is on one-over par after those costly bogeys on eight and nine.

Ben Dirs
BBC Sport following Rory McIlroy at Royal Troon

If you thought the view from the 10th tee was scary, on 11 they're essentially aiming at a forest of gorse. Oh, with a railway line running down the right. If this course hadn't existed for aeons, you'd never invent it.

-4 Patrick Reed (15), Rory McIlroy (10), Soomin Lee (9)

-3 Justin Thomas (16), Robert Rock (6), Matt Jones (6)

-2 12 players including Ross Fisher, Danny Willett and Rickie Fowler

-1 15 players including Jamie Donaldson, Justin Rose and Bubba Watson

Selected others:

E Colin Montgomerie (18) & Jordan Spieth (11)

+1 Padraig Harrington (14) & Jason Day (10)

+5 Shane Lowry (12)

+11 David Duval (18)

+14 Sandy Lyle (18)

View the full leaderboard here., external

South Korea's Soomin Lee has joined leaders Patrick Reed and Rory McIlroy on four-under-par.

The 22-year-old is making his major debut at Troon.

He turned professional in 2014 and was ranked 1,529th in the world last May.

But he is now ranked 90 and won the Shenzhen International in April.

One to watch this week.

Image source, Getty Images

Well, co-leader Rory McIlroy is motoring along and appears seemingly untroubled by a par-four 10th that has caused problems for those before him on the turn.

He takes a smart par, while Bubba Watson registers a sloppy five. The American drops a shot after under-hitting his par putt attempt.

Meanwhile, a superb long putt from Korea's joint-leader Soomin Lee gives him a par on the ninth.

Ben Dirs
BBC Sport following Rory McIlroy at Royal Troon

The view from the tee box at 10 is enough to make most hackers pack up and go home. Sand and gorse and a big hill just about sums it up. We think the drives were good...

Image source, PA

Spare a thought for amateur Scott Gregory. At just 21 years of age he was four under after 10 holes. Talk about a dream come true.

Then...

Triple bogey, bogey, triple-bogey, birdie, bogey, bogey, double bogey, bogey.

He's probably in the bar and is seven over. Unlucky. He's probably learned more in eight holes than in 21 years.

Danny Willett scrambles his way out of the rough onto the fairway and then finds the green, but he is left with a difficult putt to save par on the 10th.

The Englishman is unable to salvage it and drops his first shot of the day to move to two under.

The back nine has proved the undoing of a few this morning.

"Bunkers to the left and right make a narrow entrance to the pear-shaped green, so it becomes essential to take a club, which, if well-struck, will find the centre of the putting surface."

That's what the hole guide says of number 14 - named Alton. It seems Louis Oosthuizen cares little for such a cautious outlook on life. Boom. Ace.

At 178 yards it averaged 3.1 strokes in 2004, Louis is ensuring this year's average ends lower. Get. In. The. Hole.

Perhaps this exhibition game ahead of the tee off this week got his short game sharp.

Image source, Getty Images

We have our first ace of the Championships.

Louis Oosthuizen with a towering tee shot on the 14th, it pitches just in front of the hole and bobbles in.

Incredibly that is the South African's second hole-in-one in a major this year after an ace at the Masters., external

I wonder when Louis got his first ever hole-in-one? Let us know when you achieved your first ace by tweeting #bbcgolf.

Image source, Getty Images

Andrew Neill: My first was on the 8th at Kingsbarns aged 23. First of 3 (so far) but a bit lucky as was miles away till the slope grabbed it....

DS Weinstein-Linder: First birdie on first hole (120 yards) at Foxhills' par 3 course (Surrey) on 5th November 1994 aged 9. Remember 5th November!

There can't be many better ways to earn a living when the weather is like this...

Image source, Getty Images

But not everyone is having a great time...

Image source, Getty Images

And we've seen caddies will stop at nothing to read the line. What won't they do for their eight percent of the winnings?

Image source, AP

Justin Thomas sighs in relief as his putt finds the edge of the hole and drops in, but it's a double bogey for the American.

Thomas was leading, but having fallen away on the 15th it's now Rory McIlroy who joins Patrick Reed and Soomin Lee at the top.

The Northern Irishman had the chance to move into an outright lead with a birdie putt, but it's par and a share of first spot.

Image source, Getty Images

Masters champion Danny Willett reaches the turn in 33.

Three birdies, six pars, nice and steady from the Yorkshireman, who is two shots off the lead.

We are yet to hear from his brother and regular Twitter contributor PJ.

Let's be hearing you!