[1] De Los Santos began 2010 back with the Stockton Ports and was promoted to the Double-A Midland RockHounds where he spent most of the season.

On May 20, after just 6 innings pitched in 5 appearances in Triple-A, De Los Santos received his first major-league call-up to the Athletics when Brandon McCarthy and Tyson Ross were placed on the disabled list.

[2] However, since both injured pitchers were in the team's starting rotation, De Los Santos was sent back down again four days later without having made an appearance to make room for the promotion of a starter, Guillermo Moscoso.

[4] In his major-league debut on June 4, De Los Santos faced one batter, the Red Sox's Jed Lowrie, and struck him out.

[6] In an unexpected move, the Athletics decided to keep De Los Santos with the team when Balfour returned from leave, because their bullpen had been depleted in the previous night's 14-inning game, designating backup infielder Andy LaRoche for assignment instead.