As McIlroy warms up, Lowry and caddie go on ice

Shane Lowry and Dermot Byrne after their 2015 WGC Bridgestone Invitational win

Shane Lowry’s nine-year relationship with his caddie appears to have run its course but Rory McIlroy is determined to rekindle his love affair with the Claret Jug after battling his way into contention for The Open at Carnoustie.

The Co Down man refused to shrink from challenging conditions yesterday, impressively carding a second successive 69 in persistent rain to go into the weekend tied for sixth, just two-strokes behind leaders Zach Johnson and Kevin Kisner on four-under par.

But while Greystones’ Paul Dunne also made the cut, finishing a shot inside the mark on two-over after a 73, Lowry's decision to replace caddie Dermot Byrne with his coach Neil Manchip for yesterday's second round was a massive bombshell that speaks volumes about how frustrated he has become with his game.

The Clara man (31) said at the Irish Open two weeks ago that his patience was "wearing thin" after going seven months without a top-10 finish and that he would sit down at the end of his US season to make some changes.

"I'm going to probably have to change something," Lowry said at Ballyliffin. "I don't know what that's going to be... I've been waiting and I've been trying to be as patient as I can for the last year and a half or so, but my patience is wearing thin."

Byrne and Lowry have not gelled well recently and while a definitive split has not been confirmed, it appears that Thursday’s opening 74 brought things to a head.

According to sources close to the Lowry camp, Byrne suggested that he might not be the best man to help Lowry make the cut yesterday and Manchip, who is also the Golfing Union of Ireland’s National Coach, stepped in as an emergency measure.

It made little difference as Lowry battled hard all day before bogeys at the 16th and 17th killed off his chances he carded a two-over 73 to finish on five over and miss the cut in The Open for the fourth year running.

While he did not speak after his round, a spokesman confirmed that the three-time European Tour winner and world number 90 will have a new caddie on the bag for next week’s RBC Canadian Open.

"Shane and Dermot have decided to take a break from working together for the upcoming schedule of tournaments in the US," his spokesman said in a statement. "We are currently exploring a number of options and a new caddy will be in place for the RBC Canadian Open next week."

Lowry is under pressure to keep his PGA Tour card as his three-year exemption for winning the 2015 WGC-Bridgestone Invitational runs out at the end of this season.

Ranked 167th in the FedEx Cup standings, he will play four events in a row — the RBC Canadian Open, the Barracuda Championship in Reno, the US PGA in  St. Louis and the Wyndham Championship in North Carolina — in an attempt to make the top 125 who keep their US cards.

He was bitterly disappointed after opening with a three-over 74, commenting: “I’m not enjoying my golf at the minute, and my golf is not really enjoying me and that's the way it is, and it's hard to take."

His double-bogey six at the 10th, where he flew the green with a wedge and took four to get down from there, may have been the final straw.

He said: “From 104 yards to make double, in a tournament like this, it’s just such a kick in the you-know-what. You can’t really expect to try and compete."

Byrne and Lowry are close and the caddie has undoubtedly been as frustrated as the player recently.

Lowry has often struggled to get into the right frame of mind for tournaments but he felt this week that he had more purpose to his practice after a heart to heart with both Byrne and Manchip on the trip to Scotland.

"I feel like I have been flat for a while," Lowry said on Wednesday, explaining why he was trying to hit more hold off shots and get away from a draw that was threatening to become a hook at times.

"I feel like I need something. I don't know what I need. I need a bit of guidance. Dermo sat down looking at numbers and went back to what we were doing when I was playing my best.

"I did hit the ball with more of a neutral flight. It just gives me something to work on. It's given me a reason to go to the range. I've been going to the range, having nine holes of practice, playing okay and I just felt I needed something else."