Portstewart - Rory McIlroy's British Open preparations were in disarray on Friday after the former world number one missed the cut at the Irish Open for the fourth time in five years.
Defending champion McIlroy was one under for his round with two holes to play but a double-bogey six on the 17th ended any chance of his playing all four days, leaving him one-over-par 73 for the second round.
That saw the current world number four, five shots shy of the projected four-under cut-off mark in the $7 million event.
"My short game in general is not good as I am making silly mistakes, so it is not good," said McIlroy, who claimed a stunning victory last year at the K Club after struggling in previous years.
"I am just not being very efficient with my scoring and that is why I am making it difficult for myself."
Playing partner Jon Rahm showed McIlroy how it was done in just his second regular European Tour event, the Spaniard carding 67 to finish 12 under par, a shot behind halfway leaders American Daniel Im and France's Benjamin Hebert, who also both hit 67.
As the event host, McIlroy will remain over the weekend to hand the trophy to the new champion.
He will then cross the Irish Sea on Monday in readiness for next week's Scottish Open and follow up with the British Open a week later at Royal Birkdale.
McIlroy has not contested the Scottish event since 2014 when he shot a new course record 64 in round one.
"The Scottish Open does now take on more importance," said the Northern Irish golfer on the comeback trail after a rib injury.
"I'd like to get a good tournament under my belt going into Birkdale and while every tournament is important to me coming up in this summer stretch.
"I haven't played a lot and every time I go and play, I need to make the most of it.
"Unfortunately, the last three outings since coming back from injury hasn't been quite that way."
Rahm, who contested the first two rounds alongside McIlroy, believes the Irish golfer will bounce back in time for Royal Birkdale.
"Rory played great golf tee to green and he was just unlucky to miss some putts," said Rahm.
"He must have had 10 to 15 putts out there with just so many of those either lipping out or just grazing the hole and there are weeks like that when that happens.
"If a few of those went in then your whole attitude changes and while it was unfortunate for him, his game is in great shape and nothing to panic about.
"I know the Irish fans will be disappointed he is not here for the weekend but looking ahead to the Open, he will be just fine."
Both Im and Herbert are not only seeking a first European Tour victory but also a place at the British Open.
But Im, competing on the main Tour for a first full season, did not seem concerned whether he makes his major-championship debut.
"I'm pretty comfortable whatever happens," said the 32-year-old. "I'm pretty chill. No stress. I'm from California. That's just how it is, isn't it."
Herbert, 30, capped his round with three birdies in succession from his third hole as he seeks a maiden Tour victory.
"My driving, definitely has been the key as I again hit a lot of fairways," he said.
"Also my putting, because you need to hole some putts to have so many birdies."
World number two Hideki Matsuyama, the third member of McIlroy's group, was also in contention with a 68 moving him to nine under, along with fellow Japanese Hideto Tanihara, after a bogey-free seven-under-par 65.
Leading second-round scores from the Irish Open at Portstewart Golf
Club, Northern Ireland, on Friday, par 72 (GBR/IRL unless stated):
131 - Daniel Im (USA) 64-67, Benjamin Herbert (FRA) 64-67
132 - Jon Rahm (ESP) 65-67
133 - Ryan Fox (NZL) 67-66, Matthew Southgate 65-68, Oliver Fisher 65-68
134 - Paul Peterson (USA) 67-67
135 - Hideto Tanihara (JPN) 70-65, Hideki Matsuyama (JPN) 67-68, Anthony Wall 67-68, David Drysdale 66-69
- Peter Uihlein (USA) 69-67, Soren Kjeldsen (DEN) 68-68, Fabrizio
Zanotti (PAR) 67-69, Stephen Gallacher 67-69, David Horsey 67-69, Paul
Dunne 67-69, Jamie Donaldson 66-70
137 - Andrew Dodt (AUS) 71-66,
Haydn Porteous (RSA) 71-66, Tommy Fleetwood 70-67, Lee Slattery 69-68,
Padraig Harrington 68-69, Adrian Otaegui (ESP) 68-69, Bradley Dredge
68-69, Justin Rose 67-70, Wade Ormsby (AUS) 67-70, Dean Burmester (RSA)
70-67, Ashley Chesters 70-67
138 - Ian Poulter 68-70, Matthew Fitzpatrick 66-72
142 - Graeme McDowell 67-75, Rafael Cabrera-Bello (ESP) 69-73 (both missed cut)
145 - Rory McIlroy 72-73 (missed cut)
146 - Thomas Pieters (BEL) 73-73 (missed cut)
149 - Lee Westwood 76-73 (missed cut)