It’s tough to replace something beloved. When the Mariners traded JP Sears (and Juan Then) for reliever Nick Rumbelow this offseason, it was as big a blow as an exchange of minor league pitchers can be. Sears was sexy, boasting video game strikeout rates in the low minors after doing the same in college. Rumbelow was the replacement, whose proximity to the majors made him more appealing for Jerry Dipoto and the Mariners. A nerve issue in his neck has held him out since early March, halting his designs on an Opening Day roster spot, but today he returns to live pitching after throwing incognito in Arizona for the last month or so.
The Rainiers have activated RHP Nick Rumbelow from the disabled list and he is available to make his season debut tonight. Also, a catcher swap: added Garrett Kennedy from Modesto, sent Manny Pazos to extended.— Mike Curto (@CurtoWorld) June 5, 2018
It’s not so much that Rumbelow is a dominant high-leverage reliever (although he has the stuff to be), but that he has repeatedly shown the ability to throw multiple innings as well. He works three pitches, typically - a 92-94 mph fastball that reaches 95-96 at times, an 84-87 mph split-change, and an 80-82 mph 12-6 curveball. The split-change, when properly located, is a plus pitch, as Evan Longoria discovered.
The fastball and curveball, as Jake Mailhot profiled this spring, have curiously graded at incredibly low spin rates, yet Rumbelow’s strong K% (and low BB%) numbers match the scouting appraisal that his fastball has the type of “rise” associated with guys like Nick Vincent. Rumbelow has impressed enough to be in Seattle’s top-10 prospects, albeit with the understanding that says more about the regard the rest of the system is held in than Rumbelow’s dominance.
Most importantly, with that three-pitch mix, Rumbelow has the capacity to help fill the David Phelps-shaped hole that Álex Colomé can only partially replace. We’re still likely a few weeks at least away from seeing Rumbelow at the MLB level, but with Seattle facing down the toughest stretch of their season this month, every available arm will be crucial. Best of luck to Nick tonight with Tacoma, and I look forward to his Safeco debut.