Are Darwin Barney And Brendan Ryan Having Historic Fielding Seasons?

At Baseball Reference, Barney (Cubs) has 3.3 defensive WAR while Ryan (Mariners) has 3.2. With about a third of the season left, they are on a pace to get about 4.8-4.9 defensive WAR. Here are the top 4 seasons ever:

1. Terry Turner-5.4-1906
2. Art Fletcher-5.1-1917
3. Mark Belanger-4.9-1975
4. Ozzie Smith-4.7-1989

So far this year, after Barney and Ryan, the next highest defensive WAR belongs to Yunel Escobar of the Blue Jays with 2.2