On Wednesday night against San Francisco, he sat second baseman Mark Ellis and replaced him with Adam Kennedy. Ellis had started 26 of the club's 30 games. Kennedy is 5-for-16 against Giants starter Tim Lincecum.
On Friday night against Colorado, Mattingly said he will sit catcher A.J. Ellis and give Matt Treanor a start. Ellis has started 24 of the club's 30 games and is batting .348 with runners in scoring position.