A source with knowledge of the situation believes that the Pirates would be the "single best fit" for Burnett, and that a trade involving the right-hander is likely before July 31.

ORIGINAL: Though they currently sit eight games behind the division-leading Brewers in the NL Central, the fourth-place Pirates are still looking to be buyers at the trade deadline. Acording to John Perrotto of USA Today, the Pirates are looking to make rotation upgrades at the trade deadline, with Brandon McCarthy and A.J. Burnett (yes, that A.J. Burnett) among the rotation upgrades they are considering.

Burnett, who left Pittsburgh for the Phillies last winter in a bit of an awkward split, would make perfect sense for a Pirates' team that could use a veteran starter in the absence of injured ace Francisco Liriano. Though Burnett can block trades to 21 major league teams, major league sources indicate that the Pirates are one of the nine teams on his "acceptable assignment" list, meaning that he would embrace a return to Pittsburgh if the two teams were to agree on a deal.