According to Jeff Passan of Yahoo Sports, the Miami Marlins are trading right-handed setup man David Phelps to the Seattle Mariners and receiving four prospects in return.

Phelps, 30, has a 3.45 ERA, 1.340 WHIP and has 51 strikeouts in 47 innings this year. He will be a free agent following the 2018 season.

The top prospect the Marlins will receive is 19-year-old outfielder Bryan Hernandez. MLB Pipeline has Hernandez, whom received a $1.85 million signing bonus back in 2014, as the Mariners No. 6 prospects while Baseball America doesn’t have in the top 10.

The Marlins are also getting RHP Brandon Miller (No. 16, MLB Pipeline), RHP Pablo Lopez (No. 22, MLB Pipeline) and RHP Lukas Schiraldi in the trade.

AJ Ramos, the Marlins closer, is also getting significant interest from contenders looking for a back of the bullpen option.