It's looking unlikely that Masahiro Tanaka will be posted this year which has a few ripple effects for the Cubs and their offseason plans. One example of this might be this: Mark Gonzales is reporting that the Cubs are going after Jonathan Sanchez.
There's a specific line in the Gonzales story that sticks out prominently:
The Cubs envision Sanchez as a reliever, according to a source.
A few other teams are interested in him as a starter but Sanchez has never gone over 200 innings as a starter and the closest he got was 193 IP in 2010.
Sanchez hasn't done a whole lot of relief work over his career. He's logged 722 innings as a starter and 64 innings as a reliever. Over the course of those innings he has almost identical rate statistics (his ERA is slightly lower, his K/9 is slightly higher, WHIP is about the same) but I don't think it's enough of a sample size to draw any large conclusions about how he will perform as a reliever.
So it's a little revealing that the Cubs are going after another lefty reliever perhaps in preparation of a James Russell trade. Sanchez does have very favorable LOOGY splits (.218/.313/.363 Opponents Slash vs. LHB) and he might thrive in that role.
Tanaka staying put in Japan might do wonders for Jeff Samardzija's trade market. The Seattle Mariners would make an interesting trade partner. David Price said that he wouldn't sign a long term extension if he were traded to Seattle which shuts down that avenue a bit. I think they would also be major players for Tanaka and if that gets shut down they'll be in the market for some starting pitching which is where the Cubs and Samardzija come in.
I think it's irresponsible to expect Taijuan Walker back in a trade with the Mariners but that's a system that has interesting young pitching.