PITTSBURGH -- Starlin Castro hit three doubles and a two-run home run, but the Marlins fell just short of an elusive series win, losing 6-5 to the Pirates on Bryan Reynolds' two-run, walk-off single on Wednesday at PNC Park.

Castro, the Marlins’ 29-year-old infielder, is making the most out of the end of the 2019 season. In the midst of his worst season at the plate, he’s gone on a late-season hot streak.

After the four-extra-base-hit outburst in Pittsburgh, which set a career high, he is 15-for-38 (.395) over his last 10 games, with four doubles, four home runs and nine RBIs in that stretch. His season-long OPS has gone from .676 to .715.

That’s a big change from the first part of the season, when his OPS bottomed out at .522 in late May. He’s determined to make the finish of his 2019 the thing to be remembered, and not the start.

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“I always say, the best part of baseball is trying to finish strong,” Castro said. “You can make a season, you can help the team’s [win total] in one month. I’m just trying to finish strong. I’m feeling pretty good at the plate. I’m trying to drive the ball in the air. I think that’s one of the things that they’ve helped me with a lot.

“I don’t want anybody talking about April or May or June. It’s good baseball now. I’m just continuing to play hard.”

Wednesday, Castro doubled and scored on Garrett Cooper’s double in the first inning, hit a two-run home run in the fifth, and scored the go-ahead run in the seventh when he doubled and scored on Cooper’s home run.

“He likes playing,” manager Don Mattingly said. “In this league, you see guys like that have been around a little bit. He likes to play. He wants to be in the lineup every day. He’s never worn down. Those are the kind of guys that end up being the best players, because they love to play.”

"Right when I wake up, I just want to go to the ballpark and try to play every day, try to do my best to help the team and help my teammates,” agreed Castro. "That’s part of the thing, my mentality, that’s help me a lot. I want to play every day. Thank God, I’ve been really healthy this year. Nothing’s bothering me. I’ve just come in here and tried to do my best every day.”

The hot streak has come at a key time for Castro’s future. The Marlins hold a $16 million club option on Castro for the 2020 season. But he says he hasn’t thought about what it might mean if it continues.

“I don’t try to put it in my mind,” Castro said. “I just try to finish strong. I always say, you can make a good season in one month. Things change. Continue coming to the ballpark every day and try to do my best.”

The power of Castro and Cooper had Miami in position to win back-to-back games for the first time since late July. Cooper, batting cleanup behind Castro, was 3-for-5 with three RBIs, a home run and a double.

Newly minted closer Jose Ureña blew his first save of the season when he allowed a home run, a walk and a double ahead of Reynolds’ game-ending hit in the ninth.