One night after Angels starter Jered Weaver was pounded unmercifully in a 16-6 loss to the Orioles, Lackey (8-5) yielded seven hits, walked one and struck out six.
"That's a great effort by John. I think he really showed what he does best," Los Angeles manager Mike Scioscia said. "It's a good left-handed hitting lineup, and he pitched a terrific ballgame."
Lackey is 5-1 with a 1.89 ERA over his last seven starts.
"He usually keeps us up in games, gives you a chance to win," Scioscia said. "That's something that obviously was big tonight, and we need the other four guys to keep following suit."
"I've been fielding a lot of questions, lately, with the two new guys," Lackey said. "Especially Sully, he's a guy that really wants to learn and asks a lot of questions, and that's cool. I feel like it's not that long ago I was the one asking all of the questions so it's a little bit weird in that way, but I've won a couple of games and might have a little insight for him."
Chone Figgins had three hits, a walk and two stolen bases for the Angels, who are 20-8 since the All-Star break. Los Angeles improved to 6-2 against Baltimore and clinched the season series for a sixth straight year.
The Angels scored all their runs in the third inning against Matusz (1-2), a highly touted prospect making his third major league start. Los Angeles got only three hits in the inning but took full advantage of three walks and an error.
That proved to be more than enough support for Lackey.
"We had some good at-bats off him, but anytime he got into any trouble, he minimized it real quick and shut us down and got that third out," Orioles center fielder Adam Jones said.
Matusz allowed four earned runs, 11 hits and three walks in 5 2/3 innings. The 22-year-old had a career-high seven strikeouts, including Bobby Abreu three times, but his pitch count was at 98 when he was lifted.
"After that third inning, I was able to really relax. I felt like it was the first time since I've been here, that I was able to feel comfortable and relax," Matusz said. "I was able to make good pitches from there on out."
Melvin Mora had three hits and Nick Markakis had two hits and an RBI for the Orioles, who failed to sustain any momentum from their rout of the Angels on Friday night. Baltimore has lost 11 of 15 and is 8-20 since the All-Star break.
The Angels batted around in the decisive third inning. After two walks and a single loaded the bases, Matusz walked Vladimir Guerrero and Juan Rivera hit an RBI single to center that Jones misplayed, allowing another run to score. Howie Kendrick followed with a run-scoring grounder and Robb Quinlan added an RBI single.
"I felt like I had good command today for the most part, except for my three walks in that inning," Matusz said.
The Orioles got a run back in the bottom half when Jones tripled and scored on a double by Markakis, but that was the extent of their production. Baltimore has scored three runs or fewer 15 times since the All-Star break and is 1-14 in those games.
Markakis has reached base in 35 straight games, the longest current streak in the majors and a new personal best. ... Los Angeles optioned OF Reggie Willits to Triple-A Salt Lake to make room for CF Torii Hunter (groin), who was activated from the 15-day disabled list. ... Baltimore's Brian Roberts hit his AL-leading 44th double, the fourth in two games.