The Northern Irishman was woefully out of form over the first two days at the Ryder Cup last month and broke down in tears during an interview at the end of the weekend, as Europe slid towards a record-breaking 19-9 defeat at Whistling Straits.
McIlroy said he felt he had let his team-mates down after he suffered heavy defeats in his opening three matches and was left out of the Saturday morning foursomes.
He has struggled for most of 2021 but, playing for the first time since the Ryder Cup, issued a reminder of his talent to claim his second win of the year at the Summit Club.
“It was huge, it really was,” McIlroy said when asked if his poor Ryder Cup performance fuelled his motivation to win again.
“There was a lot of reflection [in] the couple of weeks [since then]. This is what I need to do. I need to play golf, simplify it and just be me.
“I think for the last few months I was trying to be someone else to try to get better but realised that being me is enough and being me I can do things like this.”
Starting yesterday’s final round two behind leader Rickie Fowler, McIlroy shot a three-under 33 on his front nine to stay in the hunt. After a birdie at the par-four 12th, he then sunk a 34-foot putt to eagle the par-five 14th and move three clear.
Morikawa emerged as his closest challenger and, after picking up birdies on eight of his first 11 holes, the American closed with an eagle. But McIlroy parred his last four holes to secure a one-shot win and a £1.3million prize.
Afterwards, McIlroy admitted he was considering taking the rest of the year off at the end of the first two days of the Ryder Cup after he suffered two heavy defeats alongside Ian Poulter and then Shane Lowry, with each lasting no longer than 15 holes.
“On the Saturday night of the Ryder Cup I was done with golf,” admitted McIlroy, who secured a singles victory over Xander Schauffele on the final day at the event.
“I did not want to see golf again until 2022. Sunday night at the Ryder Cup I thought, ‘Go to Vegas, go to CJ and try to build on this little bit of a breakthrough that I have had’.”
McIlroy, who also won the Wells Fargo Championship in May, is the 39th player to achieve the feat of winning 20 PGA Tour titles. He moves back into the world’s top 10 at No8.
“To get to 20 wins here is a big achievement,” he said. “I did not know if it was going to be this week, but I knew if I just kept my head down and kept playing well and kept doing the right things that eventually I would get there.
“To get a win, it is great, it feels really good.”