Delcarmen was neat for a while and excelled in 2008, striking out a batter an inning and mixing a decent change and a sharp curve in with a blazing fastball. That success kind of carried over a little into 2009, but then Delcarmen's velocity dropped, his results got way worse, and it was later revealed that he was pitching through shoulder soreness. He was left off of the Red Sox's postseason roster.
Soreness behind him, Delcarmen hoped to get back on course in 2010, but this time it was his mechanics that allegedly got out of whack. His velocity didn't improve, he threw too many balls, and he wound up getting dealt to Colorado.
In Delcarmen, the Mariners have a guy who, since the beginning of June in 2009, has walked 57 guys and struck out 64 over 90 innings. That's very unacceptable. The reason he's getting a look, though, is that he turns just 29 next week, and still has most of the repertoire that once made him good. Effective Delcarmen threw his fastball in the mid- to high-90s, with decent command. Ineffective Delcarmen threw his fastball in the low- to mid-90s, with worse command. The secondary stuff is the same. If the problem with Delcarmen last year was mechanical, then it's worth giving Carl Willis a chance to try and figure it out. The upside is really pretty high.
Again, as with all non-roster invites, the odds are against Delcarmen making a strong positive contribution. But it's easy to see the chance, and Delcarmen's been good more recently than, say, Chris Ray. So this is a move I support. You don't find a lot of relievers with three potential big league-quality pitches. Delcarmen's a gamble, but he's also intriguing.
Obligatory Manny Delcarmen fun fact: Baseball America called Delcarmen one of the Red Sox's top ten prospects for five consecutive years, from 2002-2006. He's been ranked ahead of Clay Buchholz, Jed Lowrie, Frank Francisco, Freddy Sanchez, Jorge de la Rosa, and Jon Lester.