Garrett Anderson hit his first home run this season, a 408-foot two-run pinch-hit homer that gave the Dodgers the lead in the seventh. But the Reds rallied for the win.
"When you have a lead late, you have to win the ballgame," said Torre. "It was just a one-run lead. But if you expect to do well, you have to protect that lead and get the game to [Jonathan] Broxton."
Manny Ramirez left the game in the sixth with a right calf strain. Torre said he could miss a minimum of two games.
Los Angeles starter Vicente Padilla allowed four runs, three earned, and eight hits in six innings. He struck out eight and did not walk a batter.
"Padilla, I thought, had the best stuff he had all year," said Torre. "That was as close to last year as I've seen him. I thought his stuff was really good tonight."
Padilla retired 13 straight batters in one stretch.
Padilla, however, would like to have three pitches back -- two throwing errors and an Eephus pitch that the Reds' Jay Bruce launched into the Dodgers' bullpen for a two-run home run that put them ahead, 4-3.
"How many home runs do you see with that pitch?" said Padilla. "Today it happened that way. I was throwing that pitch throughout the game and it was successful."
Things began well for Los Angeles, which rudely greeted Leake in the first inning.
Matt Kemp singled and Andre Ethier followed with his fifth home run, a two-run blast to right-center that put the Dodgers ahead 2-0. It's the first time this season that Ethier has homered in back-to-back games.
Kemp's single extended his hitting streak to 11 games.
Padilla's first throwing error allowed Chris Dickerson to reach. He later scored on Joey Votto's sacrifice fly to make the score 2-1.
The second error, a high throw after fielding Leake's sacrifice-bunt attempt, loaded the bases with one out. Orlando Cabrera's infield hit scored a run to make it 3-2.
"That was a weird inning," said Torre of the fifth. "The two base hits were on 0-and-2 and 1-and-2."
Los Angeles ventured into unknown territory on Thursday facing Leake, who was making his third start since becoming just the 21st player since the First-Year-Player Draft was instituted in 1965 to reach the big leagues without a Minor League appearance.
Leake (1-0) retired 10 of 11 batters before Blake DeWitt led off the fifth with a single. DeWitt later scored on Rafael Furcal's RBI hit to extend the Dodgers' advantage to 3-1.
The lead changed hands twice, first on Bruce's bomb off Padilla in the sixth. Then on Anderson's pinch-hit homer in the seventh.
But the Dodgers' bullpen woes continued.
Hong-Chih Kuo, who was reinstated from the disabled list prior to the game, pitched one-third of an inning.
Kuo (0-1) took the loss after being charged with both of the runs that scored on Scott Rolen's two-run double off Ronald Belisario that gave the Reds a 6-5 lead in the seventh.
"He's an aggressive fastball pitcher," said Rolen of Belisario. "I wanted to make sure I was aggressive with him and tried to stay in the zone. The ball was a little up, and fortunately it got to a part of the ballpark where nobody could run it down."
Drew Stubbs made the score 7-5 with an RBI single off Belisario, who allowed two earned runs on three hits in two-thirds of an inning for his first blown save.
Francisco Cordero earned his sixth save for Cincinnati.
"We can't just expect to outhit anyone," said Torre. "We're going to have to rely more on our starting pitching. Last year our strength was the bullpen. Right now we're trying to organize it."