DUBLIN, 22 May 2016, (AFP) - Tournament host McIlroy displayed his enormous class, coming from a shot behind Scotland's Russell Knox in first hitting a 256-yard 3-wood into the 16th hole to set up birdie, and then sending a laser-like 5-wood to within tap-in distance for an eagle at the last to win by three shots with a 12-under-par total.
McIlroy, who had been on the course earlier in the day to play three holes of his third round in the weather-affected event, went into the closing 18 holes leading by three, but after Knox birdied 14 and 15 the four-time major winner found himself a stroke behind.
"The 16th hole was the turning point in the tournament for me, so to birdie that hole and go one ahead of Russell, and then to finish the way I did in hitting that 5-wood into the last, was very pleasing," said McIlroy.
"To win the Irish Open, to win your national Open, you don't many opportunities to do it. I knew I needed to take my chance and I am just glad I came up with the right shots at the right time.
"So those shots are right up there as among my career best. I go back to the 3-wood at Valhalla and I was three behind in the PGA Championship (2012), but the shot on 16 today was much better than that 3-wood.
"But in terms of shots under pressure when I needed to pull something off like that, the two are right up there with the best I've hit."
McIlroy will next tee-off on June 2 in the PGA Tour's Memorial tournament in Dublin, Ohio in what will be his last event prior to the US Open at Oakmont two weeks later.
And McIlroy intends to draw on his second shots into the 16th and the last that helped set up a 10th European Tour success and a 20th win of his professional career heading into the year's remaining three majors.
"This win means so much for my summer ahead and to get my first win of the year is great," he said.
"I kept telling myself, and anyone that would listen, my game was close and it was a matter of everything clicking.
"So maybe those last three holes today, and the second shots I hit into 16 and the last, will be the catalyst for another great summer going into the remaining three majors, the Olympics, the FedEx Cup and then later this year the Ryder Cup and holding onto my Race to Dubai title."
McIlroy earned a cheque of 666,660 euros ($748,093) to move into second place behind Masters champion Danny Willett and also into second behind the Englishman on the European Ryder Cup points table.
Willett had led after day one and was sharing the lead at the end of day two but over the third and fourth rounds produced a run of 24 pars.
However, it all turned pear-shaped for Willett, as he posted three bogeys and a 70th-hole double bogey in a round of 77 to slip to a share of 23rd place at one under par.
Knox, who had to borrow a driver over the last three days after cracking the face of the one he had used to win last year in Shanghai, was full of praise for McIlroy.
"It was disappointing for me to bogey 16 but the way Rory played those shots into 16 and the last he really deserved to win," said Knox.
"He won the tournament, and I didn't lose it.
"But then the good thing for me is that I will have a new driver next week and also Rory's not playing at Wentworth (smiling)."
Germany's Martin Kaymer produced the lowest score of the final round with a seven-under-par 65 to share fifth place at six under.
Leading final round scores at the Irish Open on the par 72 Palmer Course, K Club, Straffan, Co. Kildare, Ireland on Sunday:
276 – Rory McIlroy (NIR) 67-70-70-69
279 – Bradley Dredge (WAL) 71-70-72-66, Russell Knox (SCO) 75-66-70-68
280 - Matthew Southgate (ENG) 70-69-73-68
282 – Martin Kaymer (GER) 69-73-75-65, Maximilian Kieffer (GER) 77-68-70-67, Tyrrell Hatton (ENG) 72-68-72-70
283 – Eddie Pepperell (ENG) 71-70-76-66, Rafa Cabrera Bello (ESP) 72-71-70-70
284 – Rikard Karlberg (SWE) 73-73-72-66, Thorbjorn Olesen (DEN) 72-72-74-66, James Morrison (ENG) 70-76-69-69, Lee Westwood (ENG) 72-72-70-70, Sebastien Gros (FRA) 71-70-73-70, Jamie Donaldson (WAL) 71-70-72-71, Gregory Bourdy (FRA) 72-73-68-71, Richard Sterne (RSA) 72-68-71-73