Marte was hit on the front of his helmet by Clarke Schmidt's 94 mph fastball in the second inning. The pitch knocked off the helmet. Marte stayed down for a few minutes and was replaced by Lewis Brinson.
Urena, a candidate for Miami's postseason bullpen, was hit on his pitching hand by a 103.9 mph line drive from AL batting leader DJ LeMahieu with one out in the third. Urena crumpled over in pain and stayed down in front of the mound before exiting the game. He was replaced by Daniel Castano.
After the game, a 5-0 Miami win, the Marlins said Urena suffered a nondisplaced ulna fracture in his right forearm, and Marte had a bruised left ear.
"Kind of your biggest fear on a day like today,'' Marlins manager Don Mattingly said. "You hate to be playing your guys almost.''
Miami acquired Marte from Arizona on Aug. 31. He is hitting .245 with four homers and 13 RBIs in 28 games with the Marlins.
Urena was among 18 Marlins sidelined with COVID-19 early this season. He is 0-3 with a 5.40 ERA in five starts since his season debut Sept. 7.
Information from The Associated Press was used in this report.