Rickie Fowler and Xander Schauffele share the lead after equaling the lowest score in the majors with a pair of 62s.
Notorious for his slow start in the majors, Rory McIlroy’s 65 represented a huge improvement for the Northern Irishman as he looks to end his nine-year wait for a fifth major.
The former world No 1 equaled the best nine-hole score of his major career when he fired five birdies to reach the halfway point in 30.
He added another at the 15th before carding his only bogey of the day when he took two attempts to get out of the rough on the 18th.
The Northern Irishman sits at five under par alongside Brian Harman with former champion Dustin Johnson and Whyndham Clark a shot better at six under.
Round two tee times – Today (June 16)
All times are local (Pacific Time), add three hours for Eastern Time and eight hours for British Summer Time
USA unless stated, (a) denotes amateurs
Starting from 1st:
06:45 Nicolas Echavarria (Col), Ross Fisher (Eng), Paul Haley II
06:56 (a) Nick Dunlap, Nick Hardy, Samuel Stevens
07:07 Romain Langasque (Fra), Taylor Pendrith (Can), (a) Aldrich Potgieter (Rsa)
07:18 Abraham Ancer (Mex), Victor Perez (France), Andrew Putnam
07:29 Keegan Bradley, Padraig Harrington (Irl), Phil Mickelson
07:40 (a) Mateo Fernandez (Arg), Guillermo Mito Pereira (Chi), Emiliano Grillo (Arg)
07:51 Joo-Hyung Kim (Kor), Sahith Theegala, Cameron Young
08:02 Sam Burns, Dustin Johnson, Keith Mitchell
08:13 Patrick Cantlay, Tony Finau, Jordan Spieth
08:24 Min-Woo Lee (Aus), Justin Suh, Davis Thompson
08:35 (a) Ben Carr, Mackenzie Hughes (Can), Taylor Moore
08:46 Frankie Capan, Patrick Cover, (a) David Nyfjaell (Swe)
08:57 (a) Christian Cavaliere, Alex Schaake, Austen Truslow
12:15 Berry Henson, Hank Lebioda, Ryutaro Nagano (Japan)
12:26 (a) Wenyi Ding (Chn), Jordan Smith (Eng), Michael Kim
12:37 Lucas Herbert (Aus), Scott Stallings, (a) Preston Summerhays
12:48 Ryan Armour, Jens Dantorp (Swe), Patrick Rodgers
12:59 Thomas Pieters (Bel), (a) Gordon Sargent, Aaron Wise
13:10 Bryson DeChambeau, Tyrrell Hatton (Eng), Francesco Molinari (Ita)
13:21 Sergio Garcia (Spa), Tom Hoge, Sepp Straka (Aut)
13:32 Jason Day (Aus), Rickie Fowler, Justin Rose (Eng)
13:43 Si-Woo Kim (Kor), Matt Kuchar, Patrick Reed
13:54 Viktor Hovland (Nor), Jon Rahm (Spa), Xander Schauffele
14:05 Stewart Cink, Martin Kaymer (Ger), (a) Michael Thorbjornsen
14:16 Paul Barjon (Fr), David Horsey (Eng), (a) Brendan Valdes
14:27 Kyle Mueller, Jordan Gumberg, (a) Bastien Amat (Fra)
Starting from 10th:
06:45 Brent Grant, Charley Hoffman, Vincent Norrman (Swe)
06:56 Simon Forsstroem (Swe), Carlos Ortiz (Mex), (a) Maxwell Moldovan
07:07 Thriston Lawrence (Rsa), Eric Cole, Adam Schenk
07:18 Alejandro Del Rey (Spa), Luke List, Wilco Nienaber (Rsa)
07:29 Harris English, Adrian Meronk (Pol), Joaquin Niemann (Chi)
07:40 Wyndham Clark, Austin Eckroat, Alexander Noren (Swe)
07:51 Cameron Davis (Aus), Russell Henley, Kurt Kitayama
08:02 Sam Bennett, Matthew Fitzpatrick (Eng), Cameron Smith (Aus)
08:13 Brian Harman, Billy Horschel, Chris Kirk
08:24 Brooks Koepka, Hideki Matsuyama (Japan), Rory McIlroy (NIrl)
08:35 Taylor Montgomery, Nick Taylor (Can), Sebastian Munoz (Col)
08:46 Olin Browne Jr., David Puig (Spa), (a) Karl Vilips (Aus)
08:57 JJ Gray (Eng), Corey Pereira, (a) Isaac Simmons
12:15 Deon Germishuys (Rsa), (a) Omar Morales (Mex), Jacob Solomon
12:26 (a) Michael Brennan, Ryan Gerard, Yuto Katsuragawa (Jpn)
12:37 Hayden Buckley, Adam Svensson (Can), Pablo Larrazabal (Spa)
12:48 Roger Sloan (Can), Dylan Wu, Carson Young
12:59 Ryo Ishikawa (Japan), Matthieu Pavon (France), Kevin Streelman
13:10 Tommy Fleetwood (Eng), Shane Lowry (Irl), Justin Thomas
13:21 Sung-Jae Im (Kor), Kyoung-Hoon Lee (Kor), JT Poston
13:32 Corey Conners (Can), Adam Scott (Aus), Gary Woodland
13:43 Max Homa, Collin Morikawa, Scottie Scheffler
13:54 Joel Dahmen, Adam Hadwin (Can), Denny McCarthy
14:05 Ryan Fox (Nzl), (a) Matthew McClean (NIrl), Seamus Power (Irl)
14:16 (a) Barclay Brown (Eng), Gunn Charoenkul (Tha), Mac Meissner
14:27 Jesse Schutte, Andrew Svoboda, (a) Alexander Yang (Hkg)
US Open 2023 – full schedule
The tournament began on June 15, and there will be a halfway cut after the second round on Friday (June 16).
In 2011, the USGA changed their cut rule so that only the top 60 players – including ties – advance to the final 36 holes.
Tee times for Saturday will be decided after the second round, with those at the top of the leaderboard going out last.
That process will be repeated for Sunday’s final round, which is on Father’s Day (June 18).
In the event of a play-off, there will be a two-hole aggregate play-off rather than sudden death. The USGA did not dispense with their tradition of an 18-hole Monday play-off until 2018.
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