U.S. Open champion Rory McIlroy refused to back down in his Twitter spat with broadcaster Jay Townsend after safely making the cut in the Irish Open on Friday.
A second round 68 put him on 138, six behind new leader Marcel Siem of Germany who fired a 66 for the second day running.
Northern Irishman McIlroy did, however, explain why he had responded so acerbically to Townsend's criticism on Thursday of McIlroy's "shocking" course management.
Townsend's comments on Twitter - the American had endorsed a tweet that McIlroy should employ Steve Williams, Tiger Woods's former bagman, to help his course management - were interpreted by McIlroy as another attack on his caddie, Irishman J.P. Fitzgerald.
The Ulsterman said that is why he had finally snapped and told Townsend to "shut up" in a subsequent tweet response.
"It was one comment too far, I've got to stand up for my caddie," McIlroy told reporters.
"J.P. is one of my closest friends. I've had to deal with it for three years and not really say anything. He's just kept at him and at him. I just had to say something.
"I don't care if he criticises me, I can take the criticism. J.P. can't stand up for himself.
"It started in Switzerland back in 2008 and it was just one comment too far. J.P. has taken me from 200th in the world to major champion and fourth in the world."
While McIlroy had his say, Townsend decided not take the argument further.
"It was an unfortunate exchange," the former European Tour pro, working for the Golf Channel this week at Killarney, told Reuters. "I prefer to put it in the past and concentrate on the Irish Open."
Even though he trails Siem, McIlroy has not ruled himself out of adding a first Irish Open title to his maiden major honour.
"My work on the range yesterday afternoon paid off," he said. "I saw enough positive signs today to put me in a good frame of mind going into the weekend. Two rounds in the mid-60s might do it."
While McIlroy and 2010 U.S. Open champion Graeme McDowell (66) made the weekend with ease on four-under 138, it was not the case for the other two crowd-pullers.
British Open champion Darren Clarke (74) missed the cut by two strokes, while three times major winner Padraig Harrington (72) was four off the mark.
Siem leads by a stroke from Dane Soren Hansen (66) and India's Jeev Milkha Singh (70, the overnight leader.