Crosby's AAA numbers projected over a full season:
.308 Average, 30 Steals, 30 Homers, 110 Runs, 100 RBIs.
Take off at least 30% of that for the jump from AAA to the Majors, and that would put it around:
.260 Avg, 21 steals, 21 homers, 70 runs, 65 RBIs.
It could be plus or minus 30% to those numbers, so the downside is:
.200 Avg, 10 homers, 10 steals, 50 runs, 40 RBIs
Upside would be his AAA numbers.
He's a risky player, and remember Oakland does NOT have the offense they have had in previous years.