ERIN, Wis. -- Like any other player at the U.S. Open, Roberto Diaz is using the practice rounds to check out the rough and the greens and to find out where he can be aggressive and where to be patient.
Unlike most any other player at the U.S. Open, Diaz also is spending at least a little time scouting out a couch for a nap.
Diaz is next up on the alternate list and has a better-than-average chance of taking the spot that currently belongs to Phil Mickelson, who will attend his daughter's high school graduation in California and, barring a weather delay, won't make his 2:20 p.m. tee time Thursday at Erin Hills.
Diaz can't roll in at noon, though. His instructions from the USGA are to be ready for the first tee time of the day -- 6:45 a.m. -- in case an injury, illness or something else unexpected besets one of the other 155 players in the field.
"I'll get up around 4:30, have breakfast, stretch out, get ready to go to the first tee," Diaz said. "Then, there's a time in between waves where I can go back in and rest, and then wait again."
It's more than worth the trouble for the 30-year-old Mexico native who now lives in South Carolina and plays most of his golf on the Web.com Tour. He has two top-five finishes this year and currently stands at 11th on the money list.
At U.S. Open qualifying, Diaz was among the 80 players vying for five spots at Canoe Brook Country Club in New Jersey earlier this month. He was in a two-man playoff for the final spot and lost on the second extra hole. That put Diaz seventh overall on the alternate list. The first six are already in. Diaz is waiting. He has no regrets about how things went down at Canoe Brook.
"It's over," he said. "There's nothing I can do about it. I made my mistakes, but I also had some good efforts and made some putts, so, no, there's nothing I would change."
Diaz said he has never spoken to Mickelson and doesn't know him at all.
Because of a change in USGA policy, Diaz is allowed to play practice rounds on the course this year; in the past, alternates were relegated to the practice facilities.
It gives him a good sense of the place. Now, if he could only control the weather.
"I asked them, how's the weather going to be?" he said. "They said with it being Wisconsin, there are going to be a lot of thunderstorms, either way; they just don't know when."