The Pirates first baseman called for time during an at-bat in the third with Johnson already in his windup. The big lefty didn't take kindly to that, and the two began to exchange words.
Moments later, both benches and bullpens rushed the field. Things settled down, but not Johnson's arm. He walked Mientkiewicz, committed an error and walked in a run to give the Pirates an early one-run lead.
It was just what the Bucs needed to propel them on their way to a 5-3 win over the D-backs and a split of the four-game series.
"I'm not going to say much about it, but those things happen, especially when it's hot outside," Mientkiewicz said. "I just asked to get set in the box. Obviously, when pitchers get started it's hard for them to stop.
"I'm not trying to get anybody hurt. I don't get many at-bats these days, and I want to at least be ready when I get one."
Johnson had a different twist on it.
"It's not really the storyline," he said. "It didn't bother me at all. If it would've, he'd probably be on a stretcher and I'd be out of the game."
That incident was just the start to a very colorful day at PNC Park.
In the second, D-backs third baseman Mark Reynolds had a home run taken away from him when a fan reached over the right-field fence and snagged the ball. The play was originally called a home run, but Pirates manager John Russell persuaded the umpires otherwise.
Which was much to the dislike of Arizona manager Bob Melvin, who was ejected for arguing the reversal.
"A fan reached over and [I could], obviously, see that his glove was over the fence," Russell said. "Would it have hit the stands or hit the fence? Fortunately, I think they got the call right. It, obviously, saved us a run."
The Pirates went on to string together four innings with at least one run. The offense, which scored five times despite no extra-base hits, was enough for Zach Duke and Pittsburgh's bullpen.
Duke, who has been the Pirates' most consistent starter since the beginning of the season, used his sinker to pitch six-plus innings, allowing only two runs on five hits. He not only out-dueled Johnson on the mound, but at the plate as well, connecting on a single in the fourth.
"I think he did an outstanding job in a game where he's facing one of the better left-handed pitchers in the game," Russell said. "He got the ball on the ground, and when he does that, his sinker is working very well.
"He's forcing contact, which is a good sign for Zach. That's what he wants to do. He's not a big strikeout guy. But it all centers around the sinker and he's been throwing."
The start was an example of how far Duke has come since last year. Many questioned the young lefty's ability after tumultuous 2006 and 2007 seasons, where he failed to live up to his fabulous rookie form in 2005.
"It's more confidence than anything," Duke said. "It's just been a feeling that I can come in and just put my plan in action. Let my pitches work for me. I'm down in the zone for the most part. I think that's been key."
Pirates reliever Tyler Yates escaped another tough late-inning situation in the eighth when he got catcher Miguel Montero swinging through strike three with the bases loaded.
Closer Matt Capps took control from there with a 1-2-3 ninth to record his 15th save of the year.
The Pirates were able to split the series despite being shut down by Arizona aces Brandon Webb and Dan Haren in the first two games. It shows, Russell said, just how far this team has come in 64 games.
"To come back and win two against a division-leading team is very good," Russell said. "It gets us in a good position again. It's great that when we lose a couple games they don't change their focus and came back and won two games."
Todd Krise is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.