Darnell McDonald will be starting in left field in place of Daniel Nava. Nava is dealing with a sore left hand.
Scott Podsednik, getting the call in center field, will now lead off.
Valentine had already rearranged the lineup a bit after the Red Sox dropped their first two games of the weekend against the Nationals.
Catcher Jarrod Saltalamacchia is back in the batting order, but both Kevin Youkilis and Mike Aviles will take a seat.
Adrian Gonzalez is shifting back to first base, and Ryan Sweeney joins Podsednik and McDonald in the outfield.
Nick Punto will take over at short, and Will Middlebrooks will look to continue his powerful hitting as he starts at third base.
On the mound for the Red Sox on Sunday is Jon Lester (3-4, 4.64). Although Lester's numbers have taken a hit, he's at times been one of Boston's best pitchers. He gave up eight hits in his last outing against Baltimore but limited the damage to two runs.
His counterpart, Jordan Zimmermann (3-5, 2.82), has gone at least six innings in all 11 of his starts this year. After allowing just one earned run in each of his first four outings, he's been tagged for as many as four in a couple of recent games. He can work deep and rack up strikeouts when needed, though, so he'll be a handful for the Sox.
Here are the complete lineups for Sunday afternoon.
Red Sox (29-30)
Scott Podsednik CF
Dustin Pedroia 2B
Adrian Gonzalez 1B
David Ortiz DH
Jarrod Saltalamacchia C
Will Middlebrooks 3B
Ryan Sweeney RF
Nick Punto SS
Darnell McDonald LF
Jon Lester P
Nationals (34-23)
Danny Espinosa 2B
Xavier Nady RF
Ryan Zimmerman 3B
Michael Morse DH
Adam LaRoche 1B
Ian Desmond SS
Tyler Moore LF
Jesus Flores C
Roger Bernadina CF
Jordan Zimmermann P
