Garrett Cooper doubled, singled and hit a go-ahead three-run homer in the eighth inning as the Miami Marlins beat Pittsburgh 6-4 Thursday night and extended the Pirates’ losing streak to 10 games.Trailing 4-1, the Marlins rallied against Pirates relievers Dauri Moreta and Carmen Mlodzinski in the eighth. Moreta allowed a leadoff double to Jonathan Davis and then walked Luis Arraez and Jorge Soler.Mlodzinski (0-1) relieved Moreta and gave up a two-run single by Bryan De La Cruz. Jesús Sánchez reached on a fielder’s choice before Garrett drove Mlodzinski’s first pitch over the wall in right-center.“Just get a fastball and get it in the air,” Cooper said. “The pitch was down, but that’s my strong suit.”After consecutive losses that finished their three-game series against Toronto, the Marlins again moved 10 games over .500 at 43-33.“It’s a different feel this year than I’ve ever been in the clubhouse,” said the 32-year-old Cooper, the Marlins’ longest-tenured player. “You felt the game was still close at 4-1. You feel it every night. That you’re not out of any game.”Arraez went 1 for 3, and his major league-leading batting average slipped a point to .397.“You create energy when you get back-to-back hits or a walk and a hit,” Marlins manager Skip Schumaker said. “You start feeling it a little bit. And I said this earlier, when you come from behind early in the season, you can do it in the middle of the season or late.”Marlins starter Braxton Garrett struck out a career-high 13 over seven innings and allowed three hits and two runs, one earned, but didn’t figure in the decision. It was the longest outing of the season for Garrett, who has allowed two earned runs in his last three starts.“Just proud of the way I’ve adapted,” Garrett said. “I feel I’ve turned into a completely different pitcher than when I was drafted.”Huascar Brazoban (2-1) got the final out in the eighth, and A.J. Puk closed with a scoreless ninth for his 10th save.Pirates starter Mitch Keller limited Miami to one run and five hits and struck out six in seven innings.“Great outing by Mitch, that’s exactly what we needed,” Pirates manager Derek Shelton said. “He executed pitches. Frustrating that we weren’t able to finish it for him.”Carlos Santana hit a game-tying double in the fourth, stole third and raced home on Marlins catcher Nick Fortes throwing error to give Pittsburgh a 2-1 lead.The Pirates increased their lead on rookie Henry Davis’ first career homer — against Andrew Nardi — leading off the eighth. After Nardi retired the next two batters, Ke’Bryan Hayes connected with another solo shot.The Marlins struck first on Joey Wendle’s sacrifice fly in the second. Cooper doubled and advanced on Jon Berti’s infield single before Wendle lifted a drive to deep center.ARRAEZ IN ALL-STAR VOTINGArraez’s performance in the first half of the season is getting the attention of All-Star voters. Arraez attracted the highest vote total among NL second basemen when the first phase of All-Star Game voting closed Thursday. The major league batting leader and Atlanta’s Ozzie Albies are the finalists for the position. The top vote getter will be announced at the conclusion of Phase II voting next Thursday.ROSTER MOVEThe Pirates placed OF Bryan Reynolds on the 10-day injured list (retroactive to Tuesday) because of lower back inflammation and recalled RHP Cody Bolton from Triple-A Indianapolis.TRAINER’S ROOMPirates: 1B-DH Ji Man Choi (strained left Achilles) will begin rehab games with Double-A Altoona.Marlins: RHP Matt Barnes (left hip impingement) threw a bullpen session Thursday. INF Jean Segura (left hamstring strain) did running drills on the field before the game.UP NEXTRHP Luis Ortiz (1-3, 4.30) will start the second game of the series for the Pirates on Friday, while the Marlins will go with LHP Jesús Luzardo (6-5, 4.09).