CINCINNATI _ Giancarlo Stanton's aim was truer than Tom Koehler's.
While Stanton threw out two runners with pinpoint-accurate throws on Sunday, Koehler's throwing misfire on a potential inning-ending double play came back to haunt him in the Marlins' 6-3 setback to the Reds.
The loss prevented the Marlins from completing their first sweep of the Reds in Cincinnati in 14 years.
Koehler gave up three home runs.
But none of those pitches proved as costly as his throwing miscue in the fifth when the Reds stretched a 2-1 lead into a 4-1 advantage.
With runners at the corners and one out, Koehler fielded Joey Votto's bouncer. But he overshot his throw to Dee Gordon at second for the force, and the Reds capitalized, with Billy Hamilton scoring from third on the play and the Reds adding another run on Scooter Gennett's RBI single.
Koehler's record fell to 1-5 while his ERA held steady at 7.92, higher than only Bartolo Colon's 8.19 ERA among Major League starters who have thrown at least 40 innings.
The long ball continues to be a problem for Koehler, who has given up 15 homers in 55 2/3 innings. His average of 2.42 home runs allowed per nine innings is the fourth-worst figure in the Majors.
The Marlins struggled offensively against Reds rookie Sal Romano, who was making only his fourth big-league start and brought a 7.50 ERA into Sunday.
The heart of the order for the Marlins _ Stanton, Christian Yelich, Justin Bour and Derek Dietrich _ combined to go 1 for 11. Romano held the Marlins to three total hits over six innings. One of those was an A.J. Ellis solo homer. But the 23-year-old right-hander retired the final seven batters he faced before yielding to the bullpen.
Miguel Rojas and Marcell Ozuna made it 6-3 in the seventh with back-to-back RBI singles off Reds reliever Michael Lorenzen. But the Marlins could get no closer.
