OAKLAND -- For the second time in two weeks, the A's have bolstered their pitching staff, courtesy of the Kansas City Royals.

On July 14, Oakland acquired veteran starter Homer Bailey from Kansas City for minor-league infielder Kevin Merrell. Now the A's have added some bullpen help, trading for left-hander Jake Diekman in exchange for minor-league outfielder Dairon Blanco and minor-league pitcher Ismael Aquino, neither of whom were ranked among Oakland's top 30 prospects by MLB Pipeline.

"We've talked for a while about wanting to add to the bullpen," said A's general manager David Forst. "Jake was someone we had engaged with in the offseason as a free agent and he's pitched really well for Kansas City. The first thing that jumps out at you is the fastball velocity -- 96, 97 (mph) every time out. He's pitched well against right-handers. I think it's a good compliment to what we have in the pen."

As Forst noted, Diekman features a mid-to-high 90s fastball along with a mid-80s slider and can be a dominant presence on the mound. The 32-year-old has notched 63 strikeouts in just 41 2/3 innings this season, a rate of 13.6 strikeouts per nine innings.


While Diekman's 4.75 ERA and 1.34 WHIP are not all that impressive, his advanced metrics have been terrific. He boasts a FIP (fielding independent pitching) of 3.37 and is limiting opponents to a .212 batting average.

"He's a tough customer," said A's manager Bob Melvin. "He's a guy that certainly misses some bats. ... Watching left-handers around the league have to deal with him, it's certainly not a comfortable at-bat. It makes us a lot better. This is a guy we've targeted here for a little bit, finally got it done, and we're glad to have him."

Diekman has actually been equally tough on lefties and righties this year, allowing a sub-.700 OPS against both, meaning Oakland doesn't have to use him solely as a left-handed specialist.

"It allows me to match up a little bit more so with (Ryan) Buchter too and maybe get a key left-hander out a little bit earlier," Melvin said. "This is one of those lefties that you kind of just run through an inning a lot of times and not worry too much about the matchup. I think this guy was sought after by quite a few teams so I think we were lucky to get him."

Diekman joins Buchter, Liam Hendriks, Lou Trivino, Blake Treinen, Yusmeiro Petit, and Joakim Soria as Oakland's primary late-inning options. Diekman, Hendriks, Trivino, and Treinen all throw in the high-90s.

"I think (he) compliments the guys in our pen right now," Forst said. "When you're talking about the seventh, eighth inning and giving Bob some options to mix and match, I think when you can bring velocity from both sides, it gives him some really good choices."

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Even after adding Diekman and Bailey, Forst made it clear the A's aren't done seeking trades. Oakland would still like to add another starting pitcher and possibly another reliever.

"We still have other conversations going on," Forst confirmed. "I have not put my phone away. We'll continue to be busy. Obviously, getting something done takes two sides, so I can't guarantee anything by Wednesday. But we're going to continue to try."