One of the groups that he didn't face: the Milwaukee fans. That happened Saturday night.
Hader came on in relief in the top of the seventh inning against the Los Angeles Dodgers. As he jogged in from the bullpen between innings, a smattering of fans stood and applauded. Most fans saved their reactions for Hader's introduction by the PA announcer a couple of minutes later, and it was a resoundingly positive one. The majority of them rose to their feet, erupting into a gradually rising roar of support.
"[I was] focusing on my job, not trying to let anything in the past haunt me, and not be a distraction," Hader said. "This is what I love to do, and it helps me clear my mind. That's really what I did today."
As the crowd cheered, Hader stood behind the mound, appearing to collect himself before stepping to the rubber to face Logan Forsythe. Forsythe struck out swinging, spurring another roar from the home crowd, whose support did not go unnoticed by the reliever.
"It means a lot," Hader said. "Having Milwaukee's support, just knowing that they know my true character. Just forgiving me for my past, because that's not who I am today."
Such a reception could not have been assumed after the hard-throwing lefty found himself in a firestorm this week over tweets he posted when he was 17 that had racist, misogynist and anti-gay overtones. The messages were exposed while Tuesday's All-Star Game in Washington was being played.
"The fans definitely, they showed their support, for sure," Brewers manager Craig Counsell said. "I heard it. I'm sure Josh heard it."
On Friday, Hader made a tearful clubhouse apology to his teammates and coaches, met for over two hours with baseball's vice president for social responsibility and inclusion, Billy Bean, and addressed the media, with his teammates joining him in the interview room at Miller Park in a show of solidarity. He did not pitch in that night's game.
While Hader was grateful for the home fans' response, he knows things might not be as comfortable when the Brewers head out on the road.
"I'm not expecting that everybody is going to forgive me early," Hader said. "But I just hope that people see my true character today, and I hope that I can show them that that's not who I was."
On Saturday, Hader allowed a two-out double to Matt Kemp but escaped with a scoreless seventh inning. He then struck out the side in the eighth, finishing with four whiffs during his two scoreless innings.
That helped preserve Milwaukee's 4-2 win. Hader now has 10 games this season in relief with four or more strikeouts, the most of any pitcher in the majors. The Yankees' Chad Green had the most such games in baseball last season with 11, the first reliever to crack double digits in that category since Rob Dibble, Duane Ward and Tom Henke all did in 1989, according to Baseball-Reference.com.
Hader, 24, is 2-0 with a 1.44 ERA, seven saves and 93 strikeouts in 50 innings. That Hader flashed his typically dominant stuff despite the emotions of the past few days was no surprise to Counsell.
"We had all the confidence in the world Josh was going to pitch well," Counsell said. "He's pitched very well all year, he was an All-Star, he's a really good pitcher. Coming into the second half, he's going to be really important for us."
The Brewers snapped a seven-game losing streak with the win and moved within 2½ games of the Chicago Cubs in the National League Central. Before the skid, the Brewers held the lead in the division for just over a month.
"It's nice to finally get a win under our belt," Hader said. "We're going to keep rolling with this."