Lynn won his 10th straight decision, allowing one run and five hits in seven innings Wednesday to lead the Cardinals over the Cincinnati Reds 4-2.
Lynn (5-0) struck out five and walked two, improving to 10-0 in 10 starts and one relief appearance since losing to Milwaukee on Sept. 7. He became the NL's first five-game winner.
"It's early -- but it's fun so far," Lynn said.
He was 6-0 with a 1.48 ERA through May 7 last season, then went 12-7 with a 4.46 ERA the rest of the way.
Leading the NL Central at the start of May for the sixth straight year, St. Louis has won six of its last nine.
"To be able to pitch like this and win games, it feels good," Lynn said. "I just go out there, concentrate and keep trying to improve every day."
Lynn retired the leadoff hitter six times. He also slapped a fifth-inning single to break out of an 0 for 52 slump. In addition, he set down a perfect bunt in the sixth inning.
"That bunt, that's what I'm most happy abut," he said.
St. Louis manager Mike Matheny applauded Lynn's, "bulldog tenacity."
"He just goes out there and does his job," he said. "The starting pitching has been a constant for us and he's helped lead the way. You can't ask the starters to do more than they've done."
Lynn retired the first four and last five hitters he faced.
"We had opportunities, but he pitched out of it," Cincinnati's Todd Frazier said. "We're scuffling a little bit, but you've got to give him credit."
Homer Bailey (1-3) gave up four runs and nine hits in 5 1/3 innings. He is 3-9 against St. Louis, including 0-5 with a 6.90 ERA at Busch Stadium.
Brandon Phillips drove in both Reds' runs, hitting a solo homer in the ninth.
Beltran's fourth-inning homer was his third in the six-game homestand.
"I'm not really trying to hit homers," Beltran said. "It's one of those streaks as a hitter where every ball you hit is in the air and has a chance of being a homer."
Phillips tied the game with an RBI double in the sixth.
Allen Craig walked with one out in the bottom half, Yadier Molina singled him to second, and Carpenter's broken-bat single drove in the go-ahead run, Pete Kozma and Daniel Descalso chased Bailey with consecutive run-scoring singles.
"In that sixth inning I don't think they hit any ball solid," Bailey said. "Right now, things are just not going our way."
Beltran threw out Bailey at second in the fifth inning when the pitcher tried to stretch a single to right. ... Lynn struck out Shin soo-Choo three times. ... The Reds have won three of their last 29 series in St. Louis. ... Carpenter had two doubles in a game for the third time this season. ... Cincinnati is off Thursday after playing 20 days in a row. and starts a three-game series at Chicago on Friday. Mike Leake (1-1, 4.34) will face the Cubs' Carlos Villanueva (1-1, 2.29) in the opener. St. Louis will play four games at Milwaukee starting Thursday, when Jake Westbrook (1-1, 0.98) and Wily Peralta (2-1, 5.02) start. ... The Cardinals' seven-game errorless streak ended when Descalso allowed Jay Bruce's ninth-inning grounder to bounce under his glove.