The Pirates are scouting the Diamondbacks' bullpen, Jon Morosi tweets. It's unclear who exactly the Pirates are watching, but Morosi mentions Oliver Perez. Brad Ziegler might be another possibility, although one recent report indicated the Diamondbacks would like to keep him. Beyond that, the Diamondbacks have a very young bullpen right now.
So: Perez. Obviously, like Antonio Bastardo, Perez is a lefty, and it seems like there's enough smoke here to believe the Pirates are in fact considering lefties, even though they already have one very good one and one pretty good one. Perez has been very good for the second consecutive year, striking out 10 batters per nine innings in 2014. He's signed through 2015, but he isn't expensive at $2.5 million next season, so that second year is actually an asset, given how well he's pitched. More subjectively, it would be fun to have Perez back with the Pirates -- he isn't a pitcher I thought would have a long career, but it's 10 years after his breakout campaign with the Bucs, and despite his years in the wilderness since then, he's now going strong.