LOS ANGELES -- The Dodgers are spending more than $45 million on starting-pitchers salaries alone this year.

Chad Billingsley, at $415,000, accounts for less than one percent of that.

But lately, the 23-year-old right-hander has done the bulk of the heavy lifting. He threw seven scoreless innings Tuesday night and even added an RBI single as the Dodgers beat the error-prone Reds, 4-1.

Billingsley (4-5) has won four of his last five starts and in the Dodgers' last 15 games, his three victories are the only ones from the starting rotation. He's also the only Dodgers starter to pitch at least seven innings in the last 17 games, and he's done it twice.

So, the former first-round Draft pick seems to have become the de facto ace, even if it's a tad premature for the title to become official.

"I don't want to put that one on him," said manager Joe Torre. "His personality is such that he puts enough pressure on himself without thinking he has to be the leader of the staff."

Billingsley allowed four singles, struck out seven and walked two. He contained Adam Dunn -- who came into the game having homered in his last five games -- with a pair of strikeouts and a walk.

Billingsley encountered only one real jam in the sixth inning after a leadoff single by Corey Patterson, who stole second and went to third on a groundout. Next was Ken Griffey Jr., who was robbed of extra bases his previous at-bat by a circus catch from Matt Kemp, filling in for injured center fielder Andruw Jones.

Billingsley pitched around Griffey for a walk, deciding it was better to face 30-30 man Brandon Phillips, who bounced into an inning-ending double play with Dunn on-deck.

He has cut his ERA from 6.53 to 3.76 during this five-start stretch, but he said he has a ways to go before his confidence level matches that of the second half last year, when his 3.02 ERA after July 1 was the seventh-best in the Major Leagues.

"My stuff is better than last year, but the second half I just went out knowing I would keep the team in the game," he said. "Now things are going good, but it's still early in the season."

Billingsley explains his recent success with the typical pitching clichés about staying within himself and pounding the strike zone with command of his fastball. He said the curveball that has been elusive lately became an effective out-pitch against the Reds.

He said he's hard-pressed to explain why May is turning out so much better than the first four weeks of April (0-4).

"Maybe when I get in trouble and I'm scuffling, instead of trying to do too much, I'm staying within myself," he said.

Pitching coach Rick Honeycutt said Billingsley's rocky April was a carryover from an equally shaky Spring Training (6.85 ERA).

"Maybe in the spring he worked too much on his two-seamer and changeup, and you get working on that stuff and forget your best pitch -- his fastball," said Honeycutt.

Honeycutt conceded that Billingsley was done no favor in his first scheduled start of the year on April 2, when minutes before the start of a game against the Giants, with a storm approaching, Billingsley was scratched, then inserted in relief, only for the rains to delay the game for more than an hour. He wound up pitching one-third of an inning over nine days.

"Everything got messed up," said Honeycutt. "It took him a while to find his groove and get back to the basics. He's gone back to using his two best pitches more the last two outings, and you can see the progress."

Offensively, the Dodgers scored a pair of runs in the second inning when the Reds got sloppy on defense, former Dodgers catcher David Ross missing a throw to the plate while one run scored, and shortstop Paul Janish, whose error Monday night cost the Reds the game, unable to short-hop Blake DeWitt's infield single, setting up Billingsley's RBI hit.

In the seventh, Juan Pierre singled home Chin-lung Hu and Pierre scored when Russell Martin beat out a potential double-play grounder.

The Reds' run came in the ninth off Joe Beimel, only the second run he's allowed all year and one he didn't deserve, as Dunn reached base on a tapper to the left side that defeated the Dodgers' defensive shift. Dunn scored on Edwin Encarnacion's single, but Takashi Saito came on to strike out pinch-hitter Ryan Freel for his seventh save.