The Seattle Mariners bid adieu to one of their top minor-league prospects by shipping outfielder Tyler O'Neill to the St. Louis Cardinals in exchange for young left-handed starter Marco Gonzales.
A seller once again as the non-waiver trade deadline approaches, Miami sent right-hander David Phelps to the Seattle Mariners for four prospects, including highly regarded outfielder Brayan Hernandez.
[...] acquired by the Marlins to shore up their weak farm system were right-handed pitching prospects Pablo Lopez, Brandon Miller and Lukas Schiraldi.
The bullpen was expected to be a strength, but it faltered and the Marlins appear destined to miss the playoffs for the 14th year in a row, the longest such drought in the NL.
The Mariners shored up their bullpen at the start of a 10-game homestand that begins against the New York Yankees and leads into the trade deadline.
After a 5-1 trip following the All-Star break, the Mariners are 48-48 and 1½ games behind the Yankees in the AL wild-card standings.
The Seattle Mariners added a veteran arm to their bullpen with the acquisition of right-hander David Phelps from the Miami Marlins in exchange for four prospects.