Jerry Dipoto didn’t wait very long. The Seattle Mariners announced Thursday evening they have completed a six-player trade with the Tampa Bay Rays. Incoming are right-hander Nate Karns, lefty C.J. Riefenhauser and outfielder Boog Powell. Heading to Tampa are infielder-outfielder Brad Miller, first baseman Logan Morrison and right-hander Danny Farquhar.

The Mariners are getting pitching depth as one half of the deal. Karns, 28 later this month, was solid in 27 appearances for the Rays this past season, 26 as a starter. He posted a 4.06 FIP and showed he can miss bats with a strikeouts-per-nine ratio of 8.9.

Karns has been an intriguing power arm since signing out of Texas Tech in 2009. He’s missed some time with injuries and that appears to have cost him a little velocity — formerly up to 97 mph. In 2015 he sat 90-94 to go with with a 78-81 mph spike curveball that was plus this past season and a fringe-average changeup in the 84-86 mph range. The curveball, being of the knuckl-grip variety, has more of a slider path to it, biting down and in on left-handed batters. As Karns has simplified his mechanics he’s been able to throw the changeup for strikes and with some sink, though the pitch lacks ideal fade.

He managed just fine versus left-handed batters this past season, though this is where his below-average control bit him on occasion as 38 of his 56 walks came versus left-handed bats. Karns throws from a higher-than-typical arm slot, which probably helps his breaking ball but may hamper the changeup, and perhaps with fastball movement. He does pitch wisely and effectively up in the strike zone, but serving up 19 long balls in 147 frames is a hefty price to pay.

The 6-foot-3, 225-pound Karns has the stuff that may play in a bullpen role and the Mariners could start camp with both roles in mind. If he remains in the rotation hes a No. 4 arm with a chance to be more based on his ability to miss bats, but whether or not he can handle a 190-200 inning workload remains to be seen. His career high is the 157 1/3 frames he tossed in 2014 before notching 147 this past season.

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Despite his somewhat-advanced age, Karns has just one year of service under his belt, making him a very cheap arm for the next two years, and one with No. 3 starter upside.

Riefenhauser, 26 in January, was a 20th-round pick of the Rays in 2010. He’s logged less than a year of MLB service — 20 total innings, to be exact, making him a rookie, still, for 2016.

The southpaw doesn’t throw hard — typically sitting 88-90 mph and mixing in an average high-70s cutter-slider, a mid-70s curveball and a changeup that flashes above average. His stuff suggests he’s a back-end starter but he came out of the bullpen for each of his 24 appearances in the big leagues the past two seasons.

He’s not likely to miss many bats and his control and command sits somewhere in the average range, so he’s not the next Mark Buehrle, either. His fly ball tendencies, however, fit better in Seattle than they in just about any other ballpark, so he has that going for him. Riefenhauser, ideally, is minor league depth once the season starts.

While Karns is the immediate key to this deal for Seattle, Powell, 23 in January, has a chance to be the best player acquired. Unlikely to reach star levels, Powell brings speed, defense and a contact-style game plan to the batter’s box. He’s been comp’d to Sam Fuld in the past, but he might be more like Chicago White Sox center fielder Adam Eaton in the end. He served a 50-game suspension in 2014 for amphetamines, but rebounded to impress in the Arizona Fall League a year ago and batted .257/.360/.364 in 56 games at Triple-A Durham after a 61-game stretch in Double-A Montgomery where he produced a .328/.408/.416 triple-slash.

His ability to make contact and handle center field to above-average levels make Powell a viable option for the Mariners as early as Day 1. He hasn’t hit for much power but the swing is short to the ball and generates line drives and hard-struck ground balls with consistency.

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Powell is not a burner — most grade his speed above average, perhaps a 55 on the 20-80 scouting scale, but he’s very good on the bases and can swipe 10-15 bags a year in full-time duty, if not more.

Powell’s best tool is his ability to force pitcher to throw him strikes. He’s very good with two strikes and adept at spoiling two-strike pitches. He’s very much a Rays or Royals kind of player, and now he’s a Mariners kind of player. Powell is the lone player in the trade not already on the 40-man roster, but if the left-handed hitter makes the club in March it could set up a nice 1-2 punch with Marte ahead of Nelson Cruz, Robinson Cano and Kyle Seager. Both make contact and can run, and both play up the middle.

Miller will provide the Rays depth at shortstop with the immediate ability to handle second base and perhaps left field, too. He may be due for a breakout season at the plate, but where he was going to fit in Seattle was unclear. I would have been fine with Miller being half of a left-field platoon while using him at other positions when he’s not in left in order to keep Ketel Marte, Robinson Cano and Kyle Seager sharp and rested.

Farquhar fell off a cliff in 2015, but showed flashes of the cutter-curveball combo that made him very good in 2014. If any club can fix him it’s Tampa (and both Chicago clubs). Morrison was a strong candidate to be non-tendered if he wasn’t traded.

What this deal tell us is if your instincts suggested to you Dipoto would go after arms early and often, you were right. This won’t be the end of it, either. But it also tells us the club has exactly zero big-league outfielders on the 40-man roster aside from Seth Smnith, who may be the most likely player to be moved this winter.

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Dipoto certainly prefers Marte over Miller at shortstop — understandably, considering Marte has almost zero experience in the outfield, and rather than dampening Miller’s value by using him in left for the most part, Dipoto dealt Miller as a player that can and will be used up the middle.

The Rays did just fine in this deal and probably landed the best current player in Miller. The Mariners stretched out their pitching depth and acquired one arm that’s sure to make the roster out of spring training and almost certainly as one of the five starters.

And in case anyone is wondering, the answer is no. No, this deal doesn’t make Taijuan Walker, James Paxton, Roenis Elias, Mike Montgomery, et al, available in trade. The price won’t change on players because other players are acquired, and you never can have too much starting pitching. None of the above, including Karns, is a proven, reliable veteran. We’ll likely see Dipoto go after that kind of arm this offseason, too.

Jason A. Churchill

Churchill founded Prospect Insider in 2006 after getting his start at He spent several years covering prep, college and pro sports for various newspapers, including The News Tribune and Seattle PI.

Jason spent 4 1/2 years at ESPN and two years at CBS Radio prior to joining HERO Sports in July, 2016.

Find Jason's Mariners podcast, Baseball Things, right here and follow him on Twitter @ProspectInsider.