Jack Cust was worth 3.0, 2.1, 1.0, and 2.4 wins above a replacement-level player in each of the last four seasons respectively. From that standpoint, it appears that his signing was a decent move. The Mariners have acquired a man who walks a lot, strikes out a lot, and hits baseballs into the seats on a semi-regular basis. However, the reason that this move is a great one rather than a good one is that Cust will probably not be playing the field as a Mariner.
Cust started more than 50 games in the outfield in three of his four years in Oakland, putting up very poor numbers. However, at the plate Cust was worth 28.2, 23.8, 9.4, and 18.8 runs. Let’s assume that Eric Wedge plays Cust in the field for a total of 50 innings in 2011, and that Cust performs about as well both defensively and offensively as he did last season. You’re looking at a ~3 win DH (or possibly more), who costs slightly more than 2 million dollars. For reference, Fangraphs.com rated Cust as being worth over 9 million last season.
Additionally, let’s not forget about who Cust replaces. Mariners DHs have been awful for a really long time. Mariners clean-up hitters have been awful for a fairly long time. Mariners hitters in general have been awful for a fairly long time. Cust wields a solid bat with enough plate discipline to walk ~90 times a season, and ideally he won’t be playing in the outfield at all this season (except in case of dire, dire need).
Jack Zduriencik went out and bought Adam Dunn Lite for 2.5 million. Even with a bit of regression due to age, we should be very happy with this acquisition.