His parents, Freddie and Yolanda, were there, but so were Brewers general manager Doug Melvin, manager Ned Yost and pitching coach Mike Maddux, anxious for their first look at the Brewers' most recent No. 1 draft pick.
No pressure, kid.
"Get used to it," Yost said later. "This ain't high school baseball any more. He's stepping into a new world."
Jeffress sounded ready for the challenge.
"It was very exciting to see a big-league ballpark, coming right out of high school," Jeffress said. "It was an honor."
Jeffress passed a physical on Friday and formally signed his first pro contract. The Brewers selected Jeffress with the 16th overall pick in the First-Year Player Draft and reportedly gave him a $1.55 million signing bonus.
The team also amended Jeffress' record in his senior season. After reporting for days he went 5-1 for South Halifax Senior High School, it turns out Jeffress was 9-1 with a 0.44 ERA, striking out 121 batters in 63 2/3 innings.
It did not take long for Tim McIlvaine, son of former Mets general manager Joe McIlvaine and a first-year scout for the Brewers, to recognize Jeffress as first-round talent.
"[I liked him] the first time I saw him," McIlvaine said. "He comes right at you with an above-average fastball. He's aggressive. Throughout the course of this year we've seen him get better with the curveball, the changeup. You can see him, whether he knows it or not, making in-game adjustments on the mound. He's just been awesome this year."
Jeffress was to return home to South Boston, Va., on Saturday and will then travel on Monday to Phoenix, where he will begin his pro career with the Brewers' rookie Arizona League affiliate.
Jenkins dropped from three-hole: Calling it "the last thing I wanted to do," Yost dropped right fielder Geoff Jenkins from his usual No. 3 spot in the lineup to No. 7 against Cardinals left-hander Mark Mulder.
"He's just been really struggling against left-handers," said Yost, who used Bill Hall in the three-hole instead. "I was just trying to get some production out of the top of the lineup right there."
But it does not appear to be a one-day move. Jenkins entered the game a career .444 hitter (4-for-9) against Mulder but was batting .143 against lefties this season. Entering Friday, Jenkins had just four hits in his last 27 at-bats, despite a 4-for-4 night on Tuesday against the Padres.
"Jenks is a guy that when he gets hot, he hits like no other player in the league," Yost said. "But, you know, during his down streaks, he struggles. Right now he's just struggling a bit. We want to keep him in [the lineup] to get him going, but we also have to find a way to manufacture a couple more runs."
Good cause: Jeffress was the first Brewers player to sign a backyard playhouse that will make others in one lucky kid's neighborhood drool.
The one-of-a-kind, Brewers-themed playhouse, which measures approximately eight-feet wide and 11-feet long, was unveiled on the field-level concourse across from section 124. Raffle tickets cost $1, and proceeds will benefit the Make-A-Wish Foundation and Brewers Charities.
The winner of the playhouse, which will be signed by other Brewers and loaded with team gear, will be selected in a drawing to be held after the Brewers-Rockies game on Aug. 24. It was constructed by the company "U Build It."
Last call: The Brewers signed four more draft picks on Friday: Right-hander Charles Hill (eighth round), outfielder Zach Clem (11th round), right-hander Johnathan King (22nd round) and right-hander Stuart Sutherland (34th round). Hill, the only high schooler in the bunch, turned down a scholarship to the University of Tennessee and instead will report to Arizona. The others will begin their careers at Helena in the rookie Pioneer League. ... The Brewers have now signed 13 of their 50 draft picks, including five of the top 10. ... Bench coach Robin Yount missed the last two games to attend his daughter's high school graduation in Phoenix, and his return flight was delayed on Friday because of mechanical issues. Yount made it back in time for Friday's game.
On deck: Left-hander Chris Capuano, 12-for-13 in quality starts this season, will take the hill for the Brewers on Saturday night against the Cardinals and right-hander Jason Marquis.
Adam McCalvy is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.