His form is improving, he said. His game is coming together. Been coming for a while now, he stressed. Thursday was the confirmation of it;  two under par in testing conditions in the first round of the Scottish Open. First page of the leaderboard. Nice.
The fact that McDowell shot 80 in the opening round in France last week - and then missed the cut - mattered not a jot. The fact that he's failed to make the weekend in 50% of the tournaments he's played in this year in his adopted home in America didn't soften his confidence. The Northern Irishman was upbeat.
He called his season "really weird". You hear this a lot, this massaging of an ugly bottom line. 'I'm playing better than I'm scoring'. That's another mantra. 'I'm not far away, I can feel it clicking. Any week now, I promise. Any week now...'
With McDowell the tendency is to accept what he's saying. He's only had two top 10 finishes in 2016 and is some distance out of the Ryder Cup reckoning, but you'll struggle to find somebody on tour who thinks he won't be at Hazeltine in September, one way or another.
McDowell is not the only go-to Ryder Cup man of the past on the outside looking in at present. Lee Westwood would have to rely on a captain's pick if the team was settled tomorrow. So would Martin Kaymer. Ian Poulter is out injured.
Others from two years ago are badly out of form. Of the 12 who won the Cup at Gleneagles, only four are in the team right now - Rory McIlroy, Henrik Stenson, Sergio Garcia and Justin Rose.
All of this can change, of course, but these are interesting times in the race for the Ryder Cup nonetheless. The cavalry you see coming over golf's hilltop is largely led by the new generation.
There are nine automatic slots in Darren Clarke's team and as it stands today, five of them are occupied by rookies. By contrast, the American team has eight automatic slots (plus four wild cards) and of the eight in pole position at the moment, only one of them - Brooks Koepka - is a rookie.
Danny Willett, Masters champion, is one of the European five. Chris Wood, winner of the PGA championship at Wentworth in May, is another.
Andy Sullivan, second in Dubai and fifth last weekend in France, is a third. Rafa Cabrera Bello, five top-eight finishes this year, is the fourth and Matt Fitzpatrick, seventh at the Masters and winner of the Nordea Masters, is the fifth rookie currently in the team.
On Wednesday, Colin Montgomerie, the victorious European captain of 2010, said no team would want any more than five rookies. Montgomerie's side in Wales had six rookies in it, but he said that's not advisable.
The last winning American team, Paul Azinger's 2008 side in Valhalla, also had six rookies. Three of them - Steve Stricker, Hunter Mahan and JB Holmes - were captain's picks.
As part of a foursome, a fourball or in the Sunday singles, Azinger's rookies contributed 12 points in their team's 16½-12½ success. Anthony Kim's days at golf's top table might have been extraordinarily brief, but they were spectacular.
At Valhalla, Kim was a revelation. Azinger didn't care that half his team hadn't played Ryder Cup before. He was fearless in going with form and he got his reward.
Was Montgomerie making too much of the rookie argument? "That's Colin's opinion, but we want the best golfers," said Cabrera Bello. "I'm close, but I'm not done yet."
Sullivan is also close. "I'm in at the moment but the next three or four weeks are going to be massive," he said. "We have the Scottish Open now and then The Open and the USPGA. Three big events.  If I don't get in automatically then I'm not getting a pick. I'm sure of that. I'm not playing for a pick, I'm playing for automatic qualification.
"There's a lot of rookies there or thereabouts. I'm sure Darren wouldn't have wanted so many in the frame but we're trying to give him as big a headache as possible. There's quite a few of us trying to show that we're ready for it. Come Hazeltine, we'll see how many of us are there and if we're ready for it or not."
McDowell is acutely aware of what he needs to do - or not do. "I'm trying my best to throttle back and be patient and not go grabbing for it," he said about his game and his pursuit of a spot on the team. He said that regardless of how many rookies are currently in the top nine, somebody like Shane Lowry would be a "hell of a pick".
Lowry - second at the US Open in June - is one of those rookies who's banging on the door a little more loudly than some of the more established names.
Thorbjorn Olesen has had four top 10s this year. Fellow Dane Soren Kjeldsen has three - including a top 10 at the Masters. Scotland's Russell Knox has had a win and two seconds since last autumn.
Sullivan was probably right when he said that Clarke would be wishing for some experienced men to find themselves again - Westwood, Kaymer and McDowell most notably - but what if they don't? What's the thinking when you have an in-form rookie on the one hand and an out-of-sorts legend on the other? Does Clarke still go with experience? How many rookies is enough? How many is too many?
"Darren wouldn't want us to make it easy for him," said Sullivan, with a smile. In the coming months, the captain is going to have some big calls to make.
Graeme McDowell was at the back of the 18th green at Castle Stuart talking about "the dangling carrot" that is September's Ryder Cup at Hazeltine in Minnesota.