LHP Jon Lester (12-7, 3.97).
VS
RHP Chris Tillman (14-4, 3.66).
Game time: 7:10 p.m.
TV/Radio: NESN, MLB Network / WEEI.
Red Sox vs. Tillman: Pedroia 6-20, Ellsbury 3-15, Nava 2-11, Salty 1-13, Ortiz 0-7, Napoli 3-8, Victorino 2-8, Carp 1-5, Drew 0-3, Middlebrooks 0-5, Ross 0-2.
Orioles vs. Lester: Markakis 14-60, Jones 14-48, Roberts 9-41, Wieters 14-39, Hardy 6-21, Davis 2-19, Valencia 2-11, Casilla 0-8, Machado 2-9, Pearce 0-6, Teagarden 1-7, Betemit 1-5, McLouth 0-4.
Stat of the Day: The Red Sox have allowed 14 runs in their last eight games. Their starters have a 1.64 earned run average in that stretch.
Notes: The Sox have won four straight and five of their last six. At 24 games over .500, they have matched their high-water mark for the season and they start the day with a 2.5-game lead in the division. The Sox also have the best record in the American League in the chase for home field advantage throughout the postseason. ... Baltimore has lost three of four and is 23-25 since the All-Star break. ... Lester is 15-2, 2.72 in 23 career starts against Baltimore. In two starts this season he has allowed five earned runs over 12 innings. Lester is 4-1, 2.31 in his last seven starts. ... Tillman has owned the Sox this season, giving up two earned runs on 11 hits over 18.1 innings. He is 3-1, 2.08 in his last six starts against the Sox. ... Ortiz is hitless in his last 18 at-bats with six strikeouts. His last hit came on Aug. 18. ... Pedroia has hit in nine straight at 15 of 35 (.429) with seven extra-base hits, six RBIs and seven runs. ... Ellsbury needs one steal for 50 this season. He would become the 24th player since 1901 with at least three 50-steal seasons. ... Salty is 17 of his last 49 (.347) with eight extra-base hits and nine RBIs.
Song of the Day: "Killer Parties" by The Hold Steady.