The runner-up finish, along with a $1 million check, moved him into the top 50 and secured his spot in the Masters and U.S. Open.
It opened the door for England veteran Paul Casey (71) to share honours atop a no-frills leaderboard with countryman Tommy Fleetwood, Brooks Koepka and Brian Harman (all 70) at seven-under after the second round at Erin Hills.
Rickie Fowler's seven-under-par on Thursday also tied the record lowest first-round score at a US Open.
"It was a good bogey though", joked Fleetwood, who regained his composure to hit a superb pitch from well below the putting surface. "So, it should be a fun weekend". "I think it's going to produce a really great champion".
Fleetwood, a 26-year-old Englishman, arrived at Erin Hills this week having missed the cut in six of the seven major championships he played, but you wouldn't know it by the way he's carrying himself.
The weekend promises to produce more incredible shots and performances as the leaderboard matures.
"It's cool, but it's just the first round", Fowler said afterwards. "Everything was in good shape". Johnson is said to have texted a message of congratulations to Harman, who in turn thanked Johnson and wrote back, "I wanted no part of you in a playoff". "The course sets up very well for me off the tee".
Former US Open champion Ernie Els chose the 20th anniversary of his last victory in the tournament to remind fans that he is not quite ready to be put out to grass. He was coasting along Friday, playing par golf and hanging out at the top of the leaderboard.
Day, at 10 over, said, "I mean, the scores were out there. For me, if I can just stay where I am, just keep doing what I'm doing, I'll have a chance".
Chez Reavie matched Matsuyama's 65 in round two to lead a group at four under.
For the first time since the Official World Golf Ranking began in 1986, Nos. "I've got four weeks off now and I'm looking forward to it very much", added Johnson, who became a father for the second time last week and will not play again until The Open at Royal Birkdale.
"I thought 63 was the number".
"There were a couple of loose swings out there, but when you shoot 65, you can take those", he said. "I struck the ball nicely, had some opportunities, rolled a few putts over the edge". "I've never done this before". "I have no idea how the weekend is going to go, no one does. I was just happy that I was the one that was able to take advantage of it today". "But I don't let it bother me". "And I was proud I hung in there".
With the cut on another low-scoring day coming at one over, Johnson seemed poised to scrape into the weekend after three birdies and a bogey left him at two under, one over outright, midway through his second round.
"The worst thing I can do is go and force it, because that's not my game. So you've got to minimize those mistakes, minimize those bogies".
"Golf's hard", Harmon said. 1, 2 and 3 all missed the cut in a major.
Fowler came back to birdie the par-3 ninth to get back to one shot back.