CINCINNATI -- Travis Wood's impressive streak of quality starts ended with another disappointment against his former team.
This one stung a little bit more.
Todd Frazier drove in a pair of runs with a sacrifice fly and a single off Wood, and the Cincinnati Reds used another big inning to beat the Cubs 5-2 on Saturday, sending Chicago to its season-high sixth straight loss.
The Cubs are last in the NL Central at 18-30, a season-worst 12 games under .500. They have their longest losing streak since they dropped seven straight last September. And they can't find a way to beat the Reds, who have won 16 of the last 18 games in their series.
"This team has some big boys, veterans out on the field, and their pitching is some of the best in baseball," Cubs manager Dale Sveum said. "It's tough to score on them. We're in all the games, but you can't add on or score on their bullpen."
They've run into a team off to its best start since 1995. The Reds have won 13 of their last 16 overall, surging to 31-18.
Cincinnati scored four times in the sixth off Wood (4-3), who fell to 0-2 in four career starts against his former team.
"It's not tougher to pitch against them," Wood said. "It's tougher to take when they beat you like that."
Homer Bailey (3-3) gave up a pair of runs in six innings to a lineup that rarely has a big inning. Aroldis Chapman had a perfect ninth for his 12th save in 14 chances, hitting 100 mph with one pitch that sailed to the backstop.
The Reds won the first two games of the series in front of sell-out crowds. The Reds are 19-5 against the Cubs over the last two seasons, including 7-1 this year.
Cincinnati won the series opener 7-4 on Friday with a five-run fourth inning that featured Ryan Hanigan's three-run homer. The catcher doubled home a run during Cincinnati's four-run sixth inning on Saturday.
The Reds didn't need any homers to pull away. Instead, they sent nine batters to the plate to stop Wood's impressive streak. The left-hander had nine quality starts to open the season, the best such streak by a Cubs pitcher since Mordecai Brown had 11 in 1908, the last time they won the World Series.
"I lost it there in the sixth," Wood said. "I didn't get away from the game plan. As good as I was feeling, I kind of got out of whack."
Frazier's RBI single tied it at 2, and the Reds pulled off a suicide squeeze to take the lead. Brandon Phillips was on third when Derrick Robinson swung at the first pitch but failed to put the ball in play, then got the sign for the bunt.
"I'm not crazy about it," Reds manager Dusty Baker said. "It's taking a heck of a chance. A lot of bad stuff can happen. He executed it perfectly. Brandon left on time."
The run put Bailey in line for the win. Hanigan's double made it 4-2, and Cesar Izturis drove him home with a pinch-hit single.
Phillips had a single that extended his streak to 12 games. Joey Votto went 0 for 3, ending his season-best streak at 12 games.
Anthony Rizzo snapped an 0-for-22 slump with an RBI double in the second inning, slapping his hands when he reached second base. Rizzo scored on Alfonso Soriano's single for a 2-0 lead.
The Reds traded Wood to the Cubs in December 2011 as part of a package for reliever Sean Marshall, who went on the disabled list with a sore shoulder before the start of the series. The 26-year-old Wood finished last season strong and had kept it up. He couldn't beat his former team, falling to 0-2 in four starts against the Reds.
The Reds got a scare in the second inning when right fielder Jay Bruce and center fielder Shin-Soo Choo banged shoulders and fell to the warning track while chasing Welington Castillo's fly ball. Choo caught it and held on, and neither player was hurt.
NOTES: Cincinnati's Johnny Cueto makes his second start since returning from the DL in the series finale Sunday. He'll face Matt Garza, also making his second start since returning from the DL. ... Rizzo singled to center in the fifth, but Choo threw him out as he tried to stretch it to a double. Rizzo then doubled in the eighth. ... The Reds had homered in each of their last nine games. ... The Cubs ended their streak of four straight games with an error.