KANSAS CITY, Mo. – Jarrod Saltalamacchia hit a three-run homer, left-hander Andrew Miller gave Red Sox Manager Terry Francona precisely what he was looking for, and Boston rolled to a 7-1 victory over the Kansas City Royals on Friday night.

Miller (5-1) allowed one run on three hits and two walks over 5 1/3 innings, rarely finding himself in any trouble against the Royals’ feeble offense. It was his first start since July 31 after a pair of appearances out of the bullpen, and his first victory since July 20 at Baltimore.

He was pulled after 83 pitches because Francona knew he’d be short on stamina. Alfredo Aceves followed up with 3 2/3 innings of scoreless relief for his second save.

Adrian Gonzalez added three hits and a sacrifice fly for Boston. Jed Lowrie had three singles, and Darnell McDonald had an RBI triple as the Red Sox piled up 13 hits.

Boston (76-48) remained a half-game behind the New York Yankees in the American League East after roughing up left-hander Jeff Francis (4-14), who has just one win in his last 11 starts. Francis was responsible for five runs on 11 hits and two walks in five innings, his second straight miserable start.

He gave up six runs in 3 2/3 innings last Sunday against the White Sox.

Jacoby Ellsbury was hit by a pitch from Royals reliever Everett Teaford in the eighth inning. He walked gingerly to first base but remained in the game, scoring on Mike Aviles’ RBI double. Ellsbury was removed in the bottom half of the inning.

Rookie DH Ryan Lavarnway, the former Portland Sea Dog who went 0 for 4 in his debut Thursday night, grounded out in the first inning and flied out in the third, leaving the bases loaded each time. He finally singled for his first big league hit in the fifth, and the Royals made sure the ball got back to the Boston dugout.

The Royals, with the youngest lineup in the major leagues, are experiencing some growing pains against the AL East powers. The Yankees won 2 of 3 against them earlier in the week, and Boston has taken the first two games of their four-game series. Kansas City (51-75) has lost 10 of 12 overall and fallen a season-worst 24 games below .500.

The Royals struck first for the second straight night when Mike Moustakas doubled into the gap in left field leading off the third inning. He moved up to third on Salvador Perez’s sacrifice and scored when Alex Gordon lofted a shallow fly ball to center.

Carl Crawford doubled leading off the fourth and scored on McDonald’s triple, and he gave Boston the lead when he came home on Ellsbury’s sacrifice fly.

Boston gave its pitching staff some breathing room in the fifth. Lowrie singled for the third straight time, Lavarnway followed with a base hit, and Saltalamacchia ripped Francis’ 0-2 pitch over the Royals bullpen in left field for his 12th homer of the season.

NOTES: The Royals have lost 4 of 5 against the Red Sox after beating them 3-1 on July 25.