The Sox sent Josh Reddick, infield prospect Miles Head (yes, the Sox gave Head for Andrew Bailey), and minor league pitcher Raul Alcantara to Oakland. In return, they received Andrew Bailey, and outfielder Ryan Sweeney.
There's nothing not to like about this move. Reddick was a decent 4th outfielder, but that's something easily acquired. Ryan Sweeney, for instance, has a .283 career average. Bailey, on the other hand, considerably improves the Red Sox bullpen. Which needed improving.
He's closed for three seasons in Oakland. And while he's never recorded more than 30 Saves in a season, that's probably because Oakland hasn't finished above .500 in the three seasons he's been out there. He's only blown 9 Saves in his career, and only 5 in the last two years. That's an 89% conversion rate, and that's not bad. Papelbon converted 88% of his Saves.
It'll be interesting to see how he handles an increased workload. He only pitched 41.2 innings last year, and 49 the year before. Again, as closer for the A's, opportunities to work are limited. He threw 83.1 innings in his rookie season and did quite well.
He doesn't have the track record of an established MLB closer, but he has done the job. Unlike say Daniel Bard. Speaking of which, it's almost a foregone conclusion that Bard will be in the rotation.
It's kind of funny how boring and frustrating this Red Sox season has been that this seems like a huge acquisition.