Boston @ Kansas City preview

Last Meeting ( Aug 20, 2011 ) Boston 4, Kansas City 9

THE STORY: Afternoons are Jon Lester's time to shine - at least, as far as this season is concerned. Lester looks to remain unbeaten in matinee action Sunday as he leads the Boston Red Sox into the finale of a four-game set against host Kansas City. The Royals, looking for a split of the series, send rookie Danny Duffy to the hill in a battle of lefthanders.

TV: 2:10 p.m. ET, NESN, Fox Sports Kansas City

PITCHING MATCHUP: Red Sox LH Jon Lester (12-6, 3.22 ERA) vs. Royals LH Danny Duffy (3-7, 5.66 ERA).

Lester isn't used to having losing months - he has posted just four of them in his six-year major-league career - but the veteran southpaw finds himself 1-2 in three August appearances despite maintaining a 3.54 ERA over that span. He was a winner last time out, limiting Tampa Bay to three hits over seven innings in a 3-1 triumph. Lester has been dominant in the daytime, going 5-0 with a 1.55 ERA in seven matinee starts.

Duffy's rookie season has featured its share of struggles. The 22-year-old had his worst outing of the season last time out, getting torched for eight runs over three innings in a 9-7 defeat at the hands of the New York Yankees. Pitching at Kauffman Stadium hasn't agreed with Duffy in his freshman campaign; he's just 1-5 with a 5.93 ERA in eight home starts.

ABOUT THE RED SOX (76-49): Boston just isn't the same team without its marquee center fielder. Jacoby Ellsbury sat out Saturday's 9-4 loss after being plunked in the back by a pitch late in Friday's victory. He's considered day-to-day with a bruised back, and manager Terry Francona may opt to give him Sunday off. Ellsbury is enjoying the best season of his career, having already established career highs in home runs (22) and RBIs (79) with more than a month left in the season. The 27-year-old has been especially hot since the All-Star break, hitting .306 with 11 homers and 30 RBIs in just 34 games. Boston battered Duffy in their only meeting, scoring six runs in 3 2/3 innings back on July 26.

ABOUT THE ROYALS (52-75): He probably won't win American League rookie-of-the-year honors, but Eric Hosmer has shown Kansas City fans he has plenty of star potential. Still just 21 years old, Hosmer hasn't looked out of place in 93 games with the big club. He had two hits and two RBIs in the Royals' eight-run sixth inning Saturday night, running his average to .271 for the season. He'll bring a perfect batting record against Lester into Sunday's series finale, having gone 2-for-2 with a walk versus the Red Sox lefty so far in his rookie campaign. The current Royals roster is hitting a collective .274 against Lester, but nobody in Sunday's lineup has homered off of him.

FINAL PITCH: Lester is 4-1 in six career starts against the Royals, and his 1.28 ERA in those outings is by far the lowest of any American League opponent.