McIlroy and Day needed low rounds to have any chance of advancing to the weekend, but both missed the projected cut by numerous shots.
When they finished their second rounds on Friday afternoon, McIlroy was 4 shots off the cut line and Day a whopping 9 shots removed.
The top 60 and ties make the 36-hole cut, which was projected at 145, 1 over par.
McIlroy is ranked second in the world, and Day is third. Both players liked the course but put their performance down to a lack of execution.
“I’m a big fan,” McIlroy said. “It’s a big golf course with lots of rough, but it lets you play.”
Danny Willett‘s tournament will end, too. Willett, who opened Thursday with a 9-over 81, withdrew Friday with a back injury.
Well another disappointing week comes to an end.. working hard to get back but the body and swing not allowing it.. sorry guys.. WD. 😔😔
— Danny Willett (@Danny_Willett) June 16, 2017
McIlroy put most of his difficulties down to lack of competitive golf. He’s twice been sidelined this year with a rib injury and since the Masters has played just the Players Championship
“I need to get competitive rounds, a card in my hand,” he said. “I was a little anxious starting out yesterday, and it caught up to me. I’m just excited to get a few rounds and start playing again.”
McIlroy has a hectic schedule again. He’s playing the Travelers Championship next week, then, after a week off, heads to the Irish Open, the Scottish Open and The Open in consecutive weeks. After another week, it’s the WGC-Bridgestone and PGA Championship.
That’s eight of the next 10 weeks after just seven starts in 2017.
Day arrived at Erin Hills a week ago and felt “I put in the best preparation for any major in my career,” he said. But he missed his first cut at a major since the 2012 PGA Championship.
“I put it in the wrong places,” he said. “I enjoyed the walk, the golf course is beautiful, but I just didn’t execute.”
McIlroy followed an opening-round 78 with a 71 and is now a combined 43 over par in 18 U.S. Open rounds since winning the tournament at Congressional in 2011.
Day added a 75 to his first-round 79, which included two triple-bogeys. His total of 154 equaled his worst two-round total at a major: The Open in 2013.
No. 1 Dustin Johnson was outside the cut line when his second round began after starting the tournament with a 75.
Since the Official World Golf Ranking began in 1986, there has never been a major championship in which Nos. 1, 2, and 3 have missed the cut.