It's still not official, but every sign points to Junichi Tazawa choosing to sign with the Red Sox. The offer the Sox made is said to be worth $6 million, and was not the biggest offer he received. But he's apparently a big Matsuzaka fan, and the Sox are perennial contenders, of course.
Now before everyone gets all excited about a new #5 starter, simmer down, have some sake, and remember that he's 22. He's at the same developmental stage as a kid drafted out of college. He'll probably start in AA Portland, and might make it to the big leagues for September call-ups.
But adding depth to the already heavy list of pitching prospects under Red Sox control is a very nice thing to see.