Run prevention was a major problem for the Milwaukee Brewers in 2012, as they ranked 13th in the National League in team ERA, ahead only of three teams that averaged more than 100 losses between them, although Milwaukee's issues were more in the bullpen (a league-worst 4.66 reliever ERA) than the rotation.
That said, Kyle Lohse does help them this year, probably by about two wins, on a contract (three years, $33 million) that seems pretty reasonable relative to market values for starters of his caliber.
If the Brewers are logical, they'll have Lohse take the spot currently occupied by Chris Narveson, who was a little above replacement level across two seasons in their rotation before missing most of 2012 due to injury. Lohse provides the Brewers with bulk innings, which Narveson can't guarantee, and would be a solid two-win upgrade over what Narveson might give them if healthy for 30 starts.
It seems just as likely, however, that the Brewers will use Lohse in lieu of Wily Peralta (the No. 73 prospect in baseball), whose spring began late after shoulder stiffness and who is less of a known quantity than Narveson or Mike Fiers; Peralta has greater upside than either of those guys, but greater uncertainty due to his lack of major league experience.
I'd rather see them roll the dice on getting above-average performance from Peralta, who has a power arm and can miss bats and generate ground balls, than on the known yet lower-ceiling quantity of Narveson. Even a good year from Peralta and the addition of Lohse doesn't put them in the class of the Cincinnati Reds and St. Louis Cardinals, but it does get them in position to pass one of those teams if either suffers a major setback.
Three years for Lohse is very reasonable given how well he pitched in the past two seasons and his track record of health. However, for the Brewers -- a team that looks like its roster is sliding out of contender status rather than improving its chances of reaching the playoffs -- it makes more sense as a contract Milwaukee could trade next offseason or in mid-2014, as the team is not likely to be very good by the time Lohse's deal reaches its final year. That said, the reported dollar figures would make him tradeable later in the contract as long as he stays healthy.
It also hurts the team to lose its first-round pick for this signing, No. 17 overall, in a draft that's pretty heavy with college starters, especially when the team's farm system already ranked as the second-worst in baseball; the Brewers' first pick this year won't be until No. 54, by which point 27 other teams will have had at least one selection, and their draft bonus pool this year will only be a little over $3 million in total.
The Cardinals benefit by picking up the first compensation pick, No. 28 overall, on top of their regular first-round pick at No. 19, which should give them an additional $1.65 million (based on the 2012 slot figures) to spend on their draft class this year. While it's not a great draft class overall, there will be several high-ceiling high school guys available with that 19th pick, and the Cards will be in great position to take a player who slid a little due to bonus demands, after which they can save some money at pick 28 or 57 by taking a player who'll sign under one of those slot numbers.