The Hunter Pence trade has the potential to turn from grimace-and-bear-it to curl-up-in-the-fetal-position-and-weep-softly in the very near future. That's because, according to, the Astros are preparing to call up outfield prospect Domingo Santana today.

Santana was literally the "other guy" — it was initially announced as a player to be named later — in the trade that brought Hunter Pence to Philadelphia. At the time, the Pence deal was billed as Jonathan Singleton, Jarred Cosart and Josh Zeid for Pence. The Phillies' top position prospect and top pitching prospect for a power-hitting right-handed bat with 2.5 years left of club control.

One can argue the Phillies could have looked for more of a rental player who would not have cost as much, but they absolutely needed a right-handed bat, and the price they ended up paying for Pence was about what you would expect.

Cosart has the makings of a solid major league starter, but I wouldn't consider him a first division top-of-the-rotation starter. In 16 starts for Houston, he has a 3.60 ERA, with mediocre strikeout and walk rates (5.9 K/9 and 3.5 BB/9). Certainly somebody who would have helped the Phillies the last couple of seasons, but not a punch in the gut.

We've long known that Singleton has a much higher ceiling, and while the first baseman is off to a slow start to his big league career: .198/.288/.374 with four home runs in 91 at bats, nobody in Houston is panicking about the 22-year-old. Still, he plays the same position as Ryan Howard, and the Phillies made a huge commitment to Howard the year before the Pence deal.

The fact that they threw in Santana was the eyebrow raiser. I remember when I first heard that the Astros had chosen Santana to complete the trade, in mid-August, how surprised I was. There were folks I talked to in the organization who absolutely loved Santana. He'd hit six home runs in 118 at bats with an .897 OPS as a 16-year-old in the Gulf Coast League in 2009, and he was OPSing .780 as an 18-year-old at Class A Lakewood the year he was traded. He was as blessed with power as any player in the system at the time, he was just years away from developing the kind of polish that would land him on the top prospect lists.

Of course, we all know what happened. Santana has torn it up the last three years in the Astros system, including this year, when he has hit .304/.383/.502 with 13 home runs in 319 at bats at Triple-A as a 21-year-old. He still has a lot of swing-and-miss in him, but he also has a ton of upside. It'll be very interesting to watch him against big league pitching. If Singleton and Santana both reach their ceilings and Cosart remains a dependable No. 3 or No. 4 starter, the Phillies' trade for Pence could turn into an all-timer. Get well soon, Tommy Joseph!