After Royals starter Yordano Ventura hit Manny Machado in the fifth inning of Baltimore's eventual 9-1 victory, the Orioles shortstop took exception and charged the mound.
He landed a solid right cross to Ventura's face as the benches emptied and the melee was halted.
There was drama of a different sort in Cincinnati, Detroit and Minnesota with the Reds, Tigers and Twins winning in walk-off fashion.
The Tigers entered the ninth inning 2-0 down against the Toronto Blue Jays, but rallied for a 3-2 win in the 10th.
The Reds coughed up a lead before recovering to claim a 7-6 victory over the St Louis Cardinals.
Brian Dozier's two-out, two-run blast in the bottom of the 11th inning lifted the Twins to a 6-4 win over the Miami Marlins at Target Field.
The Pittsburgh Pirates enjoyed two wins over the New York Mets, claiming 3-1 victories.
The Chicago Cubs went down to the Philadelphia Phillies 3-2, the New York Yankees beat the Los Angeles Angels 6-3 and the Texas Rangers edged the Houston Astros 4-3.
The Washington Nationals eased past the Chicago White Sox 10-5 and the Milwaukee Brewers overcame the Oakland Athletics 5-4.
There were also wins for the San Diego Padres (4-3 over the Atlanta Braves), Seattle Mariners (7-1 against the Cleveland Indians), Los Angeles Dodgers (4-3 over the Colorado Rockies) and Arizona Diamondbacks (5-0 against the Tampa Bay Rays).
The Boston Red Sox needed 10 innings to get past the San Francisco Giants 5-3.
CARTER THE HERO
Chris Carter was easily the best player on the field for Milwaukee's win over the Athletics. Carter went yard twice and drove in all five of the Brewers' runs. Carter is only batting .227 on the season, but now has 16 home runs. MARISNICK TAKES BRAVE CATCH
Houston right fielder Jake Marisnick made a great catch in foul territory against the Texas Rangers.
THORNBURG KEEPS ROLLING
After Brewers pitcher Zach Davies took a no-hitter into the seventh inning against the A's, the Brewers turned the ball over to Tyler Thornburg. The Milwaukee reliever pitched a perfect eighth inning and has retired 26 consecutive batters, tying Teddy Higuera for third on the franchise's all-time list. ROYALS, ORIOLES RESUME BATTLE
It will be interesting to see if cooler heads prevail on Wednesday following Tuesday's fracas. Edinson Volquez (5-5, 4.03 ERA) will take the mound for the Royals while Baltimore will start Chris Tillman (7-1, 3.33), who is off to a very good start this season.