FOX Sports’ Ken Rosenthal is reporting that the Blue Jays and White Sox are close to hammering out a deal that would involve Edwin Jackson and Mark Teahen coming to Toronto, and Jason Frasor and a prospect heading to Chicago.

Update: Jackson is being told by White Sox officials that the deal is official.

Another update: According to Dave Gershman, Moises Sierra is not in the lineup at Double A New Hampshire

Jackson is pretty close to the starting pitching equivalent of Frasor: consistent, yet unspectacular. His repertoire consists of a mid nineties four seamer, a mid nineties two seamer, a really good slider and an average changeup. Jackson’s overuse of his slider has raised warning flags in the past, but he’s thrown 200+ innings the last two seasons and is well on his way to doing so again. He’s a free agent at the end of this season and currently projects to be a Type B (barely).

But Blue Jays fans shouldn’t spend too much time getting to know him. Here’s why:

As an asset, Jackson is most valuable to a team like the St. Louis Cardinals who need a number two or three starter. And as we wait for this deal to be finalized, I’m not alone in imagining that Anthopoulos would be trying to flip Jackson before agreeing to the deal as rumoured.

Giving up Frasor and a prospect, while taking on the $5.5 million that Mark Teahen is owed next year, would all be part of the cost of doing business.

Of course, it’s impossible to bring up St. Louis without mentioning Colby Rasmus, a player who has been shopped around heavily over the last couple days. I hate to raise expectations too highly, especially given the way in which rumours involving the Toronto Blue Jays often seem to have no basis in reality, but Jackson in St. Louis and Rasmus in Toronto seem to be far too good of a fit to not mention the possibility.

It’s very likely that in addition to Jackson, the Blue Jays would throw in another of their right handed relievers (Octavio Dotel, Frank Francisco or Jon Rauch) and another prospect in order to acquire Rasmus. Earlier this week, it was rumoured that the Cardinals and White Sox were talking about a potential deal, and St. Louis’ asking price for the young center fielder was Jackson, Matt Thornton and a prospect.

Not to piss on the parade planned down friggin’ Yonge Street, but we should remember two things: 1) Nothing is for sure yet; and 2) Rasmus isn’t without risk.

As a young center fielder who has experienced success at the Major League level, with both his bat and his glove, Colby Rasmus sounds like a dream acquisition for any organization. However, there are a couple of warning signs that might scare off some suitors looking to compare his fantastic 2010 season (.366 wOBA) with his merely above average 2011 (.329 wOBA).

Most notable is his decreased BABIP (from .354 in 2010 to .291 in 2011) and HR/FB (from 14.8% in 2010 to 8.1% in 2011). While there’s some dispute as to what degree these numbers are associated with luck, a significant change in BABIP is almost always a good indicator of something else happening.

In the case of Rasmus, we can see two things leading to the lower batting average for balls in play: 1) He isn’t hitting the ball as often the opposite way; and 2) he’s getting dummied by changeups low and away far more often than last season (11.9% whiff rate in 2010 compared to a 18.1% whiff rate in 2011 on changeups).

The bad news is that any team acquiring Rasmus has to wonder why St. Louis would doubt his ability to adjust to a seemingly obvious difference in his results at the plate. On the flip side of that coin, if it’s that recognizable, any team acquiring Rasmus would hopefully be aware of it, and thinking that they have the tools to fix it.