According to the Tigers' twitter feed, the Red Sox claimed the 26-year-old AAA closer off of waivers from Detroit today. Fien, a former 20th-round pick out of Cal Poly San Luis Obispo, has spent 4 years working his way through the Tigers' minor league system before making his MLB debut last year.
In his short stint in the majors, Fien was roughed up for 10 earned runs in 11 innings. Still, his numbers in the minor leagues haven't been bad, as he posted a 3.41 ERA in AAA Toledo last year. Rather more impressive are the peripherals he's shown during his time in the minors, striking out more than a batter an inning, and walking only 2 per 9.
Fien is just the latest in a series of pitchers acquired by the Red Sox over the season to either compete for the final bullpen spot, or provide organizational depth. The most recent addition to this list before Fien, Gaby Hernandez, was designated for assignment to make room for Fien on the 40-man roster. At this point, it's hard to expect many of them to make a significant contribution, if any at all during the course of the season. Still, depth never hurt anyone.