TOWN OF ERIN, Wis. -- Nobody is paying closer attention to the "Phil Mickelson watch" than is Roberto Diaz.
The 30-year-old Web.com Tour player is the first alternate for the U.S. Open, which means he'll get into the 156-player field at Erin Hills if any player pulls out.
The most likely to withdraw? Mickelson, who has said he'll attend his daughter Amanda's high school graduation Thursday. The ceremony starts at 10 a.m. Pacific time; Mickelson's first-round tee time is 2:20 Central time.
He had not withdrawn as of Monday evening and was scheduled to appear at a pre-championship news conference Tuesday.
"Obviously, everybody is telling me that I might take Phil's spot," Diaz said after his practice round Monday. "With him, you never know. They might change the graduation. He might take a plane and get here in time, so you never know."
Diaz, a four-time NCAA Division II all-American at the University of South Carolina-Aiken, lost a playoff in sectional qualifying and is hoping to play in his first major championship. He is allowed to play practice rounds at Erin Hills.
"It's a feeling that I'm sure nobody wants to have," he said of not knowing whether he'll get in. "But it's also a good feeling because I have a lot of percentages going my way. If one guy pulls out, I'll be in.
"It would mean the world (to play). It's like I'm in Disney. I was walking in and I was feeling butterflies just looking at everything. It's the dream that everybody has as a golfer."
New arrival: Defending U.S. Open champion Dustin Johnson was scheduled to fly to Wisconsin on Tuesday, one day after his fiancee, Paulina Gretzky, was to give birth to the couple's second child.
According to ESPN, the plan was for Gretzky to have a C-section Monday.
Johnson, 32, is ranked No. 1 in the world. After missing the cut at the Memorial Tournament on June 2, he played two practice rounds at Erin Hills and said he liked the course.
Johnson didn't play in the Masters in April. He withdrew before the first round, after slipping on some steps at his rental house and hurting his back.
Like father, like daughter: Steve Stricker's oldest daughter, Bobbi, is playing in the Wisconsin Women's State Open on Tuesday and Wednesday at Racine Country Club.
Bobbi Stricker will be a redshirt sophomore on the University of Wisconsin women's team but is relatively inexperienced at tournament golf.
"I went there on Friday and walked around with her," Stricker said. "She's excited and nervous. She's going through all the stuff where she's playing in a bigger tournament for her and she's like, 'I'm not hitting it good.' She's stressing out, so I'm talking her off the edge every day, it seems like.
"It's exciting for us to watch and see how she is going to do."
Open additions: Davis Love IV and Ryan Palmer were among six players added to the field. The USGA saved six spots for those who moved into the top 60 in the world ranking Monday. Of the six, only Chris Wood (No. 60) was previously not exempt.
The other five spots thus went to alternates from sectional qualifying: Whee Kim, Gregory Bourdy, Todd Light, Palmer and Love. Diaz was next in line.
Stormy weather: With a storm moving in Monday evening, officials blew the horn to call players off the course at 6:45 p.m. Twenty-five minutes later, Erin Hills was hit with a torrential rainstorm that likely will affect playing conditions Tuesday.
Though the course is sand-based and drains well, there won't be quite as much roll-out in the fairways and the greens are bound to be a bit softer and slower.
This article is written by Gary D'Amato from Milwaukee Journal Sentinel and was legally licensed via the Tribune Content Agency through the NewsCred publisher network. Please direct all licensing questions to email@example.com.