LaRoche is known as a great second-half hitter with the Pirates, hitting .323 in the second half of 2006, .312 in the second half of 2007, and .304 in the second half of 2008, with some pretty decent second half power numbers, as well.
LaRoche is currently hitting .247 with 12 home runs and 40 RBI.
LaRoche's best season was 2006, with the Atlanta Braves, in which he belted 32 home runs, hit .285 and knocked in 90 RBI—all career highs.
Diaz is a great defensive shortstop, currently with AA Portland. This season with Portland, Diaz is hitting .253 with no home runs and 24 RBI.
Strickland is a pitcher currently with the Low-A Greenvile. This season, Strickland is 5-4 with a 3.46 ERA with one save.
You might expect more from the Red Sox for Adam LaRoche. But he is just a rent-a-player.