The Rangers' need for a starter had become desperate, as their alternative to acquiring Garza was calling David Clyde to ask if he had anything left. Garza replaces Grimm in the rotation, which would be something on the order of a 4-5 win upgrade over the course of a full season (in terms of wins above replacement), and maybe as much as 2 WAR from now until the end of the season.
Garza's main issue has been lack of health, as he's been effective when healthy but has made just 29 starts since the beginning of 2012. He's long been a four-pitch guy, but has barely used his changeup, by far his worst pitch, in 2013, and instead has increased the use of his two-seamer, a pitch he'd largely eschewed for years because he couldn't command it.
That two-seamer has good sinking life but hasn't produced ground balls this year, as Garza's ground-ball rate (39.8 percent) is his lowest since he was traded to the Cubs before the 2011 season. He helps the Rangers, obviously, but he alone won't bridge the gap between them and the Oakland Athletics, and I think they need to find one more starter.
It's also worth noting that Garza is a free agent after this season, which means the Rangers are only acquiring him for the rest of 2013 and cannot reap draft pick compensation if he signs elsewhere over the winter.
Olt's year has been derailed by vision problems that forced him to miss most of May, but prior to that the 24-year-old projected as an above-average everyday third baseman who added a ton of value on defense and hit for power with a low contact rate and modest OBP. Since coming off the DL in Triple-A, he's hitting .247/.353/.506, with 57 strikeouts in 186 plate appearances, a decent facsimile of what I expect from him in the majors, perhaps with slightly more contact when his vision is 100 percent again.
He's turned himself into a plus defender at third -- he was a bad defensive shortstop at UConn -- and the raw power is probably grade-70 on the 20-80 scouting scale, so if he can hit enough to get to that power, he has 25-30 homer potential. He's no Gary Scott, but Cub fans should be pleased.
Edwards is the wild card of the trade, boasting a very high upside with a limited track record and pedigree that belies his actual talent level. He has easy plus velocity, 90-96, with an above-average to plus curveball with good depth and 12-to-6 break, and a developing changeup that projects as average to slightly above. The 21-year-old has a 1.83 ERA with 122 strikeouts in 93 1/3 innings for low Class Hickory this year.
He's aggressive and throws strikes, with a little life on the fastball, and probably could go to high-A at this point given how well he's dominated low-A. The main issue with Edwards is that he's slight of build, atypically so for a starter, listed at 6-foot-2, 155 pounds. You have to develop him as a starter because of the chance for three pitches and the success so far, but it's fair to worry about his durability.
Grimm might be a fifth starter but right now projects more as a swingman or middle guy because he's a two-pitch pitcher, fastball and curveball, whose fastball is flat and changeup is below average. Lefties hit him particularly hard, which is saying something because righties have had their way with him this year as well, and his high BABIP isn't a function of bad luck so much as poor command and lack of fastball life. Moving to the NL may help a little, but the biggest key will be finding a usable changeup for him.
The Cubs will also receive a player to be named from a list of names on which the teams have already agreed, making the return for them even better at some point, although even without that, Olt and Edwards alone are a strong return for 10-12 starts of Garza.