PHOENIX -- Johnny Cueto leads the majors in wins and has his sights set even higher.
Cueto scattered four hits over seven innings for his 17th victory and the Cincinnati Reds beat the slumping Arizona Diamondbacks 5-2 on Tuesday night.
"All I can promise is to try and keep going because I want to win 20 games," Cueto said through a translator. "I felt better as the game went on. I was able to gather more strength and continue."
Cueto (17-4) gave up two runs, struck out one and walked five for his eighth victory in nine decisions. The right-hander lowered his NL-leading ERA to 2.48.
"He's feeling it every time he goes out there," Reds manager Dusty Baker said.
Ryan Hanigan hit a two-run single and Todd Frazier added a two-run triple for the Reds, who won for the third time in four games and stretched their lead in the NL Central to seven games over St. Louis.
Jonathan Broxton pitched the eighth and Aroldis Chapman closed it out for his 33rd save and 25th straight, tied with Texas reliever Joe Nathan for the longest active streak in the majors.
Wade Miley (14-9) allowed three runs and seven hits over seven innings. He walked one and struck out five for the Diamondbacks, who have lost five straight and seven of nine.
"The first couple of innings everything was up," Miley said. "I was able to make the adjustment, but it didn't work out."
Arizona opened a 1-0 lead in the first when Gerardo Parra doubled, went to third on a wild pitch and scored on a sacrifice fly by Jason Kubel.
But the Reds rallied in the second and flipped the momentum with a long at-bat.
Frazier led off the inning with a single and Miley got ahead of Scott Rolen 1-2. Rolen then fouled off two pitches, took a ball, fouled off two more, took a third ball and fouled off five pitches in a row before drawing a 15-pitch walk.
"I'd have rather singled on the first pitch," Rolen said.
Baker thought the battle affected Arizona's rookie left-hander.
"That took a whole inning out of him," Baker said. "Foul off a pitch, foul off a pitch -- he was trying everything. That takes a lot out of a pitcher."
Chris Heisey singled to load the bases and Frazier scored on a wild pitch before Hanigan lined a two-run single to centre for a 3-1 lead.
John McDonald reached on a fielder's choice and scored on a double to left by Parra in the fifth to pull the Diamondbacks to 3-2.
Frazier tripled home Brandon Phillips and Ryan Ludwick in the eighth against Matt Lindstrom, who was making his Arizona debut after being traded from Baltimore for Joe Saunders on Sunday.
"We were just up the one run so that little cushion was helpful," Frazier said.
NOTES: Phillips stole second in the eighth, his 11th stolen base in 12 attempts. ... Miley needed 54 pitches to get through the first two innings but threw only 53 over his final five. ... Reds RHP Mat Latos (10-4) will look to bounce back from a rough outing when he pitches Wednesday against LHP Patrick Corbin (5-5). Latos allowed seven runs and nine hits Friday against St. Louis for his first loss since July 18. Corbin will be the third straight rookie the Diamondbacks send to the mound.