BOSTON (AP) — The run support Ryan Dempster lacked in his previous two starts came in abundance Tuesday night.

Dustin Pedroia and the Boston Red Sox backed Dempster with a season-high 20 hits, giving him an early cushion that kept getting bigger in an 11-4 victory over the Colorado Rockies.

Pedroia drove in four runs on three hits and a sacrifice fly. Mike Napoli added two RBIs and every Boston batter finished with at least one hit.

Jacoby Ellsbury, Daniel Nava and Jose Iglesias had three hits apiece as the Red Sox built a big lead for Dempster after scoring just two runs in his past two starts combined.

Dempster (5-8) allowed two runs and six hits over six innings, leaving with an 8-2 lead and picking up his first victory since June 9.

Dempster got himself in and out of trouble in the first, walking Dexter Fowler to lead off the game. DJ LeMahieu’s attempt at a sacrifice bunt turned into an infield single as it rolled toward third base without a Boston player fielding it. Dempster got Carlos Gonzalez to pop out to third, then Michael Cuddyer grounded into a double play to end the threat.

Boston responded with two runs on three hits in the bottom of the first and led the rest of the way.

The Red Sox had at least three hits in every inning until the fifth, when they finally went hitless but still got a runner on base on a twoout walk to David Ortiz. It was also the first inning in which Boston failed to score after roughing up Juan Nicasio (4-4) early.

Wilin Rosario had three hits for the Rockies, including a solo homer in the second all the way out of Fenway Park. Michael Cuddyer extended his career-best hitting streak to 22 games, longest in the majors this season, with a single in the fourth. He finished with two hits.

Nicasio had his worst start of the season, lasting only 2.1 innings and allowing seven runs — six earned — on 12 hits. He walked two and struck out two. He had never allowed more than eight hits in a start this season and the Red Sox had that matched after two innings, taking a 5-1 lead with a pair of runs in the first and three more in the second.

Dempster’s only glaring mistake came in the second inning on a 3-1 slider to Rosario, who drove it out of Fenway Park for his 12th home run of the season. The solo shot cleared the Green Monster in left field and all the signs above it.