For only the fifth time all year, the Miami Marlins have lost a one-run game.

Marlins reliever Dylan Floro, beginning the ninth inning with Miami and the Chicago White Sox tied at 1-1, allowed a leadoff single to Elvis Andrus and allowed him to reach second base on a wild pitch to Tim Anderson. Floro struck out Anderson on a slider low and away, but left another slider over the plate to Luis Robert Jr. two batters later. Robert got a hold of it and slapped the ball down the left field line, driving home Andrus for the game-winning run.

While Floro had been a trustworthy set-up man for Miami in the first month of the year, he has had shaky results in the past four weeks. Since May 7, he has a 6.75 ERA and has allowed runs in four of his 14 appearances. In his first 13 appearances this year, he had only given up run(s) in one outing, posting a 1.98 ERA. Friday’s loss to Chicago was Floro’s third time allowing the winning/go-ahead run in the ninth inning since May 12.

The Marlins pitching staff had been smothering the White Sox lineup until that decisive ninth inning.

Eury Pérez, starting his sixth major league game at 20 years old, had his composure and command tested early. After going down 1-0 in the second inning from a solo home run to Yasmani Grandal, Pérez loaded the bases with no outs in the third inning by allowing singles to Andrus and Anderson, and a walk to Andrew Benintendi. It looked like the White Sox were about to blow the doors off the Marlins, with the No. 3-4-5 hitters coming up.

Instead, Pérez struck out robert on a slider low in the zone, was helped by third baseman Jean Segura when he snared an Andrew Vaughn line drive that would have scored at least two runners, and got Yoan Moncada to fly out to center field.

According to MLB.com, Chicago’s win probability peaked at 81.3% after they loaded the bases, and went down to 62.9 after Moncada’s flyout.

Pérez ended the night after five innings, giving up the one run on the Grandal home run in the second inning, striking out six, and walking two.

Marlins relievers Tanner Scott, JT Chargois, and Andrew Nardi combined for three scoreless innings. Scott has not allowed a run since May 14 (14 outings). His ERA has dropped from 4.91 to 2.90 in that span.

The lone Marlins run was a Joey Wendle solo home run to right field in the fifth inning. Wendle is on a six-game hit streak. He’s gone 10-for-23 with four doubles over that span.

Garrett Cooper (left elbow soreness) will undergo an MRI on Saturday, according to MLB.com’s Christina De Nicola, after Elvis Andrus collided with him at first base during the third inning.