The Arizona Diamondbacks bolstered their bullpen depth today, hours before the 4pm deadline, bringing back submariner Brad Ziegler from the Miami Marlins in return for right-handed reliever Tommy Eveld.

It sometimes feels like Brad Ziegler shouldn’t have a career. He throws 85 mph and doesn’t strike anybody out (at least relative to other pitchers), yet he has a 2.72 ERA over a decade-plus as a major leaguer. Ziegler’s firmly on the back end of his career — he’ll turn 39 during the playoffs — but it’s not like he has a fastball to lose. I’m convinced he could keep doing this until he’s 50 or so. I don’t usually go nuts over short-term season splits, but three runs allowed in his last 29 games is a darn good run, so you can make a good case that he’s found that special sorcery groove he thrives on.

Among relievers between 2008 and -18 (the range of his major-league career), Ziegler ranks second in baseball in terms of earned runs saved over what FIP suggests.

An extreme ground-baller, Ziegler’s is at least partly tied to the quality of the infield defense behind him. The D-backs aren’t necessarily elite by that measure, but the addition of Ziegler still counts as an upgrade. Kudos to the D-backs for recognizing that, even though the bullpen has performed well so far this season from a run-prevention standpoint, there’s actually significant downside risk. No bullpen in baseball has a larger discrepancy between their seasonal ERA in 2018 and the rest-of-season ERA projected by the FanGraphs Depth Charts.

Tommy Eveld is a tall, thin — though not in the Gumby/Sale tier — pitcher with that classic hard fastball/hard slider combo. He’s a pure relief prospect, used almost entirely that way for South Florida as an amateur. It’s hard to argue with his results so far, with a 10.3 K/9 rate against a 2.8 BB/9 and only two homers allowed in 58 1/3 innings at High-A, which is nothing to complain about in the hitter-friendly California League. He’s been a little old for his levels (he was promoted to Jackson last week), but if he continues to be successful in the high minors, he could be in the majors for the Marlins very quickly. This season would be a tad overaggressive, and Arizona was interested in an upgrade for this year’s pennant race.