"The stuff wasn't quite what it had been, the sharpness and crispness to it," manager Scott Servais said. "I do think there's a chance we could re-sign Justin and bring him back into the organization [on a Minor League deal]. I know he's going to look at his options, if he does get claimed and all that other stuff. We'd certainly like to have him back, we just didn't see it where it was at right now."
De Fratus's Cactus League ERA was at 4.50 after a two-inning outing in Tuesday's 4-4 tie with the Angels in which he allowed three hits and one run with a walk and a wild pitch.
De Fratus had several good seasons in the Phillies' bullpen from 2012-14, and he was 3-1 with a 2.39 ERA in 54 outings in '14. But he struggled to a 5.51 ERA in 61 outings last year. The California native said he knew midway through last year that his mechanics were off, but De Fratus felt he'd corrected them after some offseason work.
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De Fratus' departure leaves Seattle with 49 players in its Major League camp, including 38 on the 40-man roster.
The bullpen situation changed after two other bounceback candidates -- Ryan Cook and Evan Scribner -- were sidelined by strained lat muscles. Cook is on the 60-day disabled list and Scribner won't be back before Opening Day.
Closer Steve Cishek has been slowed by a sore biceps, but he's expected to make his first Cactus League appearance in more than a week on Thursday. After setup man Joaquin Benoit and hard-throwing youngster Tony Zych, the competition for right-handed arms appears wide open.
"Obviously when Scribner and Cook went down, that bit into our depth," Servais said. "Where we're at, there's plenty of opportunity for guys to step up. Joel Peralta has been a nice surprise. I didn't know what we'd get there and he's throwing the ball really well. He looks good, but there's competition there yet.
"I think each club in the Cactus League or Spring Training, their 25-man is not set. There's competition, and that just happens to be where ours is, along with the right-handed first-base [spot]."
Peralta, a 39-year-old veteran who came to camp on a Minor League deal, clearly is on track to claim one of the final spots. Blake Parker is another non-roster invitee in the mix along with returnee Mayckol Guaipe, while Jonathan Aro has struggled a bit this spring after being acquired from the Red Sox.
The left-handed situation is also murky with Charlie Furbush slowed by triceps tightness, leaving Vidal Nuno and David Rollins as the only healthy southpaws. Starter Mike Montgomery is being transitioned to a relief role to help there and the Mariners could well bring in other candidates -- both lefties and righties -- as other teams cut down their roster.
Servais has said the club will lean heavily on track record with some of these pitchers, but in De Fratus' case, apparently the spring performance outweighed his previous success in Philadelphia.
"You do rely on track record, but you also have to trust your eyes and what you're seeing," Servais said. "A lot goes into those decisions, from our group here and coaching staff to Jerry [Dipoto] and the front-office guys, what they're seeing when they acquired the players. There's a lot of opinions and a lot that weighs into those decisions.
"Again, there is plenty of opportunity here. You'll see Montgomery out of the bullpen today, and we'll see how that goes. Cishek is coming back tomorrow, so hopefully we'll have a better feel by the end of the week where we're at."