Alvarez and Zimmermann each dealt with pitches thrown inside, which created some excitement on a steaming hot afternoon. In the second inning, Alvarez plunked Zimmermann on the left elbow.
"It was a sinker that got away," Alvarez said. "It was two outs, the pitcher is up. It's not something I did intentionally. It's just a pitch that got away from me."
In the fifth inning, it was Alvarez's turn to dodge an inside pitch. With runners on the corners, Alvarez squared to bunt, but he had to scramble out of the way of a Zimmermann fastball.
Alvarez did get the bunt down, and afterwards looked at Zimmermann.
"He stared me down, and I turned around and said. 'Can I help you?'" the Washington right-hander said. "He didn't say anything, and I said, 'Get back to the dugout where you belong.'"
Zimmermann no-hit the Marlins on the final day of the 2014 season.
"Any time you hit the pitcher, it looks bad, right?" Miami manager Mike Redmond said. "He certainly wasn't trying to hit the pitcher on purpose."
Saturday was the first time Alvarez and Zimmermann were up at the plate this spring.
"When he's throwing at you, it kind of makes you mad a little bit and frustrated when [he should] just throw it over the middle," Zimmermann said. "You have good control, it's not like he is wild. He's always around the zone. I'm not sure if it's intentional or not, but sure seemed like it."
Nationals manager Matt Williams summed up the exchange in four simple words.
"Boys will be boys," Williams said.
As for the day overall, Alvarez had a rough afternoon. He was shaken up in the first inning on the diving stop and he experienced some discomfort after making the play.
"When I went to stand up after the play, it bothered me," Alvarez said.
Alvarez iced his left knee after his 73-pitch outing.
"He was not locating, really all of his pitches," Redmond said. "He ran into a few hits in the third inning and gave up some runs. It wasn't a great outing for him at all."