PITTSBURGH -- After launching a two-run homer that sailed out of PNC Park and bounced into the Allegheny River, Reds first baseman Derek Dietrich dropped his bat and stood in the batter’s box for a moment to admire his prodigious blast.

That didn’t sit well with the Pirates, and what happened in the fourth inning of Sunday afternoon's 7-5 Pittsburgh win didn’t appear to go over well with anybody at PNC Park.

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Right-hander Chris Archer, who gave up the home run, threw a first-pitch fastball behind Dietrich when the Reds infielder led off the fourth inning. Archer denied any intent, saying he simply “yanked” the pitch and “missed my spot.” Home-plate umpire Jeff Kellogg saw it differently and immediately issued a warning to Archer. The Reds also believe there was retaliatory intent behind Archer’s pitch, and the lack of an ejection drew the ire of manager David Bell.

“Any time another team or another player is intentionally trying to hurt one of our players, that’s the problem. It’s that simple,” Bell said. “It’s unacceptable, and we’ll always stick up for our players no matter what.

“When you hit a home run, you’re allowed to run around the bases any way you want. It’s unacceptable and unfortunate that that happened. It should never happen … for any reason. It’s completely -- it shouldn’t be part of the game. It shouldn’t be allowed.”

In the end, Bell and Yasiel Puig were ejected -- as was Reds left-hander Amir Garrett. Archer and Pirates catcher Francisco Cervelli remained in the game, but setup man Keone Kela and closer Felipe Vazquez were tossed for their role in the ruckus.

Bell emerged from the dugout to argue with Kellogg while players jawed back and forth on the field and from their respective dugouts. Kellogg walked toward Archer when he issued the warning, so Archer initially thought Bell was coming to talk to him. A handful of Pirates players jogged toward Archer to make sure the Reds weren’t approaching him.

“At first, it kind of looked like he was coming toward me. I really didn’t hear what he said,” said Archer, noticeably wearing a shirt with that read When you play Pittsburgh, you play the whole city. “I was just trying to get a new ball from the umpire. I don’t know what he was saying.”

The dugouts and bullpens eventually cleared, and there was a fair amount of pushing and shoving in the pile of players who gathered near home plate. Pirates first baseman Josh Bell got between Yasiel Puig and Archer, then Joey Votto eventually corralled Puig while Pittsburgh outfielder Melky Cabrera spoke with the Reds' right fielder. Pirates starter Trevor Williams pulled Archer out of the scrum.

Just as the fracas seemed to be clearing up, Puig charged a group of Pirates players that included Archer, Williams and Cervelli. Pittsburgh bench coach Tom Prince intervened while Reds catcher Tucker Barnhart clung to Puig’s ankle, but both sides began shouting and shoving again. Williams and Puig were in each other’s faces at one point, but Cincinnati left fielder Jesse Winker pulled Williams aside.

“Good thing punches weren't thrown. I think that would be a bad day for them with me and Puig in there,” Garrett said. “But you know, it's squashed now. We'll move forth from here. There's no hard feelings now."

Puig was upset that Archer threw at Dietrich and vented his frustration after the game. So did Dietrich.

“You don’t like to get thrown at. When someone’s throwing at someone, you’re trying to inflict pain or possibly hurt someone or send a message,” Dietrich said. “I’m just trying to put a good swing on the ball, and I did my job. I know it’s part of the game, but I’m just lucky that it couldn’t hit me anywhere that could have hurt me -- or even hit me -- but I get hit quite often and I’m not afraid to get hit, but the ball can do some damage, and I’m just trying to do damage to the baseball. That’s it.”

The Pirates mostly denied any sort of motive behind Archer’s pitch, but Vazquez said they did not appreciate the way Dietrich admired his home run.

“I think it was a little too much. He can look at it and start running. Don’t stay in there then start walking,” Vazquez said. “We all knew it was going to be far, but you don’t have to wait until the ball hits the ground then start walking. You’re not supposed to do that.”

Vazquez was uncertain why he was ejected, saying he was primarily trying to calm down other players. It may have been because he entered the scrum without wearing a jersey, the result of him rushing out of the clubhouse as Dietrich came to the plate. Pirates manager Clint Hurdle said he was told Vazquez and Kela were tossed for being “very aggressive.”

“Both of them were very aggressive, is what I was told, as were Garrett and Puig,” Hurdle said. “That’s why the guys got thrown out. Basically their actions spoke to their ejections.”

Prince’s low-stance block of the 6-foot-2, 240-pound Puig was a topic of conversation in Pittsburgh’s clubhouse after the game. Pirates manager Clint Hurdle said GM Neal Huntington shared an online post joking that the Pittsburgh Steelers were “going to reach out to him for maybe some guard play on the offensive line.

“He had a very firm foundation, I guess,” Hurdle added. “He was trying to get out there and take care of Cervelli.”

When play finally resumed, Archer struck out Dietrich.

“There was some admiration there, definitely. That’s for you guys to judge. That’s for everybody else to judge,” Archer said of Dietrich’s first home run. “I was trying to stay focused on the game. Things did kind of get out of hand, but I was just happy to punch him out two times after that.”