Once he realized he was part of a team that scored runs and played solid defense behind him, he felt relaxed enough to attack hitters and pound the strike zone.
Hultzen allowed two runs -- one earned -- on six hits over five innings to earn his first Triple-A win and Carlos Peguero homered for the fourth straight game Tuesday as the Rainiers beat the Fresno Grizzlies, 8-2.
MLB.com's No. 11 prospect struck out six batters and issued three walks in his third start since being promoted from the Southern League 10 days ago.
"It feels great. I remember my first Double-A win and this was pretty similar," said Hultzen (1-1), who throws a fastball, changeup and slider. "Obviously, this is a higher level, but my first Double-A win was also my first pro win, so I'll definitely remember that. Now I will remember this one, too."
Hultzen's first Double-A win came only 2 1/2 months ago. Selected second overall in last year's Draft, he signed late, made six appearances in the Arizona Fall League and did not debut in the Minor Leagues until April 8.
"I threw more strikes, and even though I walked three batters, that is all I can ask for," the University of Virginia product said. "I made more adjustments than I did in my other two [Triple-A] starts, so hopefully, I can go on from there."
Hultzen was 8-3 with a 1.19 ERA in 13 starts with Double-A Jackson prior to the promotion. But he surrendered five runs on five hits and five walks over three innings in his Pacific Coast League debut on June 23 in Colorado Springs, then scattered three hits over four innings of one-run ball on Thursday against Las Vegas.
Fresno reached Hultzen in the second as Jackson Williams reached on an error and scored on a sacrifice fly by Brock Bond. An inning later, Brett Pill led off with a double, took third on Charlie Culberson's one-out single and came home on a base hit by Chris Dominguez.
That was all the offense Fresno musterered against the 22-year-old southpaw.
"The level of competition is high," Hultzen said. "There are some really good hitters at Double-A, but all of those guys are in the lineup at Triple-A and they have been playing for a long time. They're more seasoned and more savvy.
"These Triple-A hitters are very patient. I had to adjust to them because they weren't going to swing at pitches in the dirt or off the plate. They squared some balls up and they yanked some balls, but that's OK."
The Grizzlies weren't the only ones hitting the ball hard.
Carlos Peguero entered Tuesday with four homers in his last three games. The Grizzlies decided to challenge him again in the finale of the four-game series, but he left the yard again leading off the second.
The blast was his 17th of the year and moved him into third place in the PCL behind Oklahoma City's Mike Hessman (26) and Iowa's Anthony Rizzo, who hit 23 before being called up to the Cubs.
The 25-year-old outfielder smacked a pair of solo homers off Eric Hacker in the opening game of the series and slugged another off Mitch Lively on Sunday. In Monday's 4-3 victory, Peguero connected for a two-run blast off big league veteran Yusmeiro Petit.
"It's awesome, he's awesome to watch," Hultzen said. "He not only puts on a show during batting practice, but he does it in the game, too. Every time he is up you wait to see what he'll do next. He's fun to watch."
Starter Jason Stevenson (2-2) took the loss after surrendering seven runs on eight hits over 5 1/3 innings. He fanned six but allowed three homers.