Red Sox 6, Astros 1: John Lackey allowed one run in six innings in his second start since 2011 and host Boston completed the four-game sweep to tie the club record for most wins in April.

Lackey (1-1) sat out last season after undergoing Tommy John surgery and hadn’t pitched since April 6 against the Toronto Blue Jays, when he lasted 4 1/3 innings before departing with a biceps injury. He gave up a run to Houston in the first inning before settling in and retiring 13 in a row, and then pitching out of a bases-loaded, one-out jam in the sixth.

David Ortiz continued his hot hitting since returning last weekend from an Achilles’ tendon injury, collecting two hits and two RBIs, and Stephen Drew had a two-run triple for the Red Sox. Daniel Nava contributed two hits and scored three runs and Mike Carp added two hits and an RBI.

Every Boston starter except leadoff hitter Jacoby Ellsbury had at least one hit off Astros starter Bud Norris (3-3), who allowed five runs (three earned) and nine hits in six innings. Ronny Cedeno and Carlos Pena had two hits each for Houston.

After a one-out double by Nava in the first followed by a walk to Dustin Pedroia, Ortiz delivered an RBI single to tie the score at 1. The Red Sox took the lead for good in the fourth when Drew tripled to deep right, driving in Carp and Jarrod Saltalamacchia for a 3-1 lead.

GAME NOTEBOOK: With a victory Tuesday at Toronto, the Red Sox can finish with their best record in the month of April in club history. … Ortiz came into the game with 24 total bases in his first seven games, the most by a Boston player since Carl Everett in 2000 (27). He also entered the game leading the majors with 15 hits since his season debut April 20. … The Astros came in averaging 10.2 strikeouts a game. They cut back to four on Sunday.