MIAMI -- A couple of the Marlins' most highly regarded prospects had their moments on Monday night, but it was the missed opportunities that proved most costly in a 7-3 loss to the Red Sox at Marlins Park.
Trevor Richards, making his Major League debut, kept the Red Sox off-guard until the right-hander ran into some tough luck in the fourth inning. Rookie third baseman Brian Anderson connected on his first big league homer, which was the only run the Marlins generated off Boston starter Christopher Johnson.
"It was a good feeling," Anderson said of his first homer, which came on his 123rd MLB at-bat. "In our park, you never really know off the bat. It's great to get the first one out of the way. Hopefully, more to follow."
Richards, 24, is the Marlins' No. 22 prospect, according to MLB Pipeline. Anderson is No. 9.
"It felt good overall," Richards said of his debut. "I wouldn't say I had my best stuff today. I battled through three [innings]. They made the adjusts when they needed to and made me pay."

The Marlins officially added Richards to their roster in the afternoon, and the former Drury University standout showed plenty of promise in his debut. He retired the first seven batters he faced, then worked out of a jam in the third inning. But in the fourth, a two-out swinging bunt by Xander Bogaerts set up a three-run inning.

After splitting four games over the weekend with the Cubs, the Marlins faced another postseason team from a year ago in Boston.
"They're kind of a different animal than we've seen through the first four [games]," Marlins manager Don Mattingly said. "It's more of an all or nothing for the Cubs. This is a little different offense, where they'll take their hits. They'll kind of ding you a little bit, and they're dangerous also."
In the fourth inning, Richards encountered more bad luck when Andrew Benintendi reached on a check-swing single, and Hanley Ramirez crushed a two-run homer. Richards worked 4 1/3 innings, allowing five runs. He struck out five and walked one.

Anderson, who drove in five runs in the four-game series with the Cubs, received the silent treatment in the dugout after his leadoff homer in the second inning. The opposite-field drive went a Statcast™ projected 384 feet, with an exit speed of 102 mph.
The 24-year-old third baseman is off to a hot start, batting .333 with a slugging percentage of .524.
"They had some fun with it," Anderson said of his teammates' reception. "It's a good time."

To the fan that caught the ball, Anderson traded an autographed bat for it.
"It's a great trade for me," Anderson said.

MOMENTS THAT MATTERED
Two on, no results: Missed chances hurt the Marlins, especially in the third, fourth and sixth innings against Johnson. Up 1-0 in the third, Miami loaded the bases with two outs. With a chance to pad the lead, Anderson swung at a first pitch and grounded to short for a forceout. After the Red Sox went up, 4-1, the Marlins put runners on first and second with no outs in the fourth inning. But after Miguel Rojas lined out, John Holaday bounced into a 4-6-3 double play. Following consecutive singles by Starlin Castro and Anderson, the Marlins couldn't advance a runner in the sixth.
"I thought all day we were able to get guys out there but weren't able to extend innings," Mattingly said. "That's a little different look, too, from their guy. He's not an overpowering guy. Late movement. Late little cut. He kind of criss-crosses the ball to both sides of the plate. So, obviously, a challenge in that. I thought we had the right idea, but we weren't able to execute. I think we chased a little out of the zone."

No. 500: Castro enjoyed a three-hit game, with two singles and a double. In the ninth inning, the 28-year-old second baseman also reached a milestone. On his groundout to first baseman Ramirez, Castro drove home Tomas Telis for his 500th career RBI. Castro also has hit safely in 13 straight games at Marlins Park.

QUOTABLE
"Offensively, I think we'll be OK. We'll battle. When we get guys back, when we get J.T. [Realmuto] back in the lineup, and when we get Martin [Prado] and JT Riddle, we'll be able to mix and match with guys with a little more experience." -- Mattingly, on getting three regular position players back from the disabled list

SOUND SMART WITH YOUR FRIENDS
After shutting out the Cubs, 6-0, on Sunday afternoon, Richards logged three straight scoreless innings on Monday, extending the Marlins' string to 12 straight scoreless innings before the Red Sox scored three times in the fourth.
WHAT'S NEXT
Anderson hit cleanup with a left-hander on the mound on Monday, and he may wind up there, with Justin Bour batting fifth, when facing southpaws. Miami faces Chris Sale at 6:10 p.m. ET on Tuesday. Marlins Opening Day starter Jose Urena looks to bounce back from a rough first start, giving up five runs in four innings in a no-decision against the Cubs.
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