Top-ranked Oklahoma State entered Regional competition with three players ranked among the top 25, including 2011 Ben Hogan Award winner Peter Uihlein. But on the first day of the Colorado Regional it was No. 70 Sean Einhaus who led the Cowboys, who fired an exquisite 12-under-par 276.

Einhaus fired a 7-birdie 66; Uihlein, Morgan Hoffman and Talor Gooch shot 70. OSU didn’t need the second-ranked player in the country’s score, an even-par 72 by Kevin Tway.

No. 13 Auburn shot a solid 280 and trails Oklahoma State by four strokes after 18 holes. The Tigers had four break par led by Niclas Carlsson’s 67. Blayne Barber, ranked eighth, shot 72.

Arizona State came in at 282 with two players, Jesper Kennegard and Scott Pinkney, shooting 69.

Weather suspended play with seven teams still on the course. Colorado State’s Zakhai Brown stood at 7-under with two holes to play. His round included a stretch of five straight birdies.

Virginia Tech Regional: Georgia Tech leads
Led by Kyle Scott’s 4-under-par 68 No. 4 Georgia Tech opened the Virginia Tech Regional with a 1-over 289 and leads Duke by six shots after the first of three rounds. Kent State and Oklahoma each shot 296 and are tied for third in the 13-team field. No. 10 LSU struggled on Day 1, shooting 17-over 305.

The top five teams from each of six regions qualify for the NCAA Championships, May 31-June 5 in Stillwater, Okla.

The Yellowjackets also got a 1-over 73 from James White and a pair of 74s from JT Griffin and Richy Werenski. Tech’s lead could have been more were it not for four bogeys and one double bogey on the par-4 18th hole.

Scott’s 6-birdie round put him in the individual lead by two shots over Oklahoma’s Abraham Ancer (ranked No. 82).

UNC-Wilmington’s Josh Brock and Payne McLeod, Campbell’s Vaita Guillaume and Duke’s Brinson Paolini all shot 71 on a day that saw just six break par.

Indiana Regional: Illinois leads by a stroke
No. 9 Illinois rolled to a 7-under 277 and leads No. 8 Alabama and Michigan by one stroke after 18 holes at the Indiana Regional.

Four Illini players broke par and the fifth score was even-par 71. 2010 NCAA medalist Scott Langley shot 3-under 68 with Luke Guthrie at 69 to lead the Illini.

Alabama’s Bud Cauley and Hunter Hamrick each shot 68.

The Wolverines got 68s from Matt Thompson and Jack Schultz. Lion Kim and Joey Garber carded 71s.

Stanford’s David Chung and Graham Brockington each shot 69 and No. 4 Andrew Yun shot a 73 for a Cardinal squad that shot even-par 284 on the par-71 course.

Thirteen players shot in the 60s, seven of them tied at the top with 68, including Iowa’s Chris Brant and Memphis’ Jack Belote.

Florida Region: Gators in front early
Six squads shot sub-par first rounds led by No. 5 Florida, who opened with a 6-under 282 and takes a one shot lead over Arkansas into Friday’s second round. Only one of the 14 squads – Jackson State (+37) – finished at more than 10-over on Day 1. Defending NCAA champion Augusta State opened with a 290 and is tied for eighth.

Florida’s Bank Vongvanij shot 4-under 68; Phillip Choi finished at 3-under and Andres Echavarria was 1-under.

Oregon’s Jack Dukeminier leads the medalist race, starting the week with a 6-under 66. His round included six birdies and an eagle.

Kennesaw State’s Ben Greene shot 67 along with Southeastern Louisiana’s Phillip Westerman. Notre Dame’s Niall Platt was among four who shot 68.

Southwest Region: San Diego State by one
San Diego State fired a 6-under 278 and leads Washington by one and Liberty by two after 18 holes at the Southwest Region. The highest ranked team in the field, No. 7 Texas A&M, shot 281 and is tied with Arizona three shots behind SDSU.

Alex Kang and Collin Featherstone each shot 3-under to lead the Aztecs, who are looking for their first appearance at the NCAA Championships since 2008.

Washington was led by Kevin Spooner’s 68 and Tze Huang Choo’s 69.

Liberty, never a participant in the NCAA Championship finals, got a 4-under 67 from Preston Dembowiak.

Twelve players broke 70 with UC-Davis’ Matt Hansen’s 64 leading the field. Oregon State’s Alex Moore shot 66.

Texas A&M’s Conrad Shindler, a member of the top 50, suffered a disastrous start at 8-over thru 11 holes including a triple on the par-5 10th. He finished at 81 and is tied for 73rd in the 75-player field.

San Diego Region: USC leads No. 2 UCLA
Southern California fired a 10-under-par 278 and leads No. 2 UCLA and No. 11 Texas by nine shots after the first of three rounds. The 15th-ranked Trojans got strong starts from Jeffrey Kang, who shot 6-under 66, and Steve Lim, who shot 68. T.J. Vogel added a 71. Kang, who leads the individual race by a shot, birdied five of his first nine holes.

The Bruins got a 69 from freshman Patrick Cantlay and a 71 from Pontus Widegren.

Dylan Fritelli (68) and Cody Gribble (70) led the Longhorns.