Baseball-Reference has a page showing the top 1000 position players by its version of WAR. This gets you down to 17.1 career bWAR, a.k.a. Mike Gallego and Cecil Fielder. (The juxtapositions created by WAR is one of my favorite of its features.) There is one current Athletic¹ in the top 1000, so let this serve as the first in an occasional series of check-ins on his ranking:

Player: Coco Crisp
Career bWAR: 30.0
Rank: 506th
Tied with: Lance Johnson, Pete Runnels
Next up: Bobby Bonilla and Chick Hafey, 30.1

Lance Johnson played 14 years in the big leagues and led his league in triples five times. His finest hour was 1996 with the Mets (7.2 WAR, a legitimate MVP-caliber season, though he only finished 18th in the voting, behind such luminaries as Eric Karros (1.3 WAR) and Henry Rodriguez (1.6)). Fully a third of his career value came from being a very good defensive center fielder, which probably made him underrated overall.

Pete Runnels played from 1951 to 1964. He began his career as a shortstop before shifting to second base and ultimately first before retiring, though he wasn't much of a fielder anywhere. He made three All-Star teams with the Red Sox and led the league in batting average twice. He finished his career with 844 walks to just 627 strikeouts. His grandson was drafted a few times, but never higher than the 29th round, and he managed just 31 innings in Rookie ball before earning his release.