Lefthand-hitting, basestealing, leadoff-type outfielders born within a nine-month span in 1982-83.
Gardner has been valued at 7.1 Wins Above Replacement (WAR) and counting over the past two seasons (2.2 and 4.9+).
Bourn has been valued at 7.4 WAR and counting over the last two seasons (4.3 and 3.1+).
Ellsbury gets a mulligan for this season, but over the two previous seasons Ellsbury was valued at 6.6 WAR (3.9 and 2.7).
Over those two-year spans, Gardner has 66 stolen bases in 238 games, Bourn has 107 stolen bases in 286 games and Ellsbury had 120 stolen bases in 298 games.
Here are UZR outfielder rankings for 2008-09:
... and for 2009-10:
Gardner remains under his team's control for another four seasons, Ellsbury for three seasons and Bourn for two seasons.
Which player has the most trade value?