PITTSBURGH — Johnny Cueto vs. the Pittsburgh Pirates is quickly becoming one of baseball’s biggest mismatches.

Cueto dominated the Pirates again over six innings, Paul Janish homered and drove in four runs and the Cincinnati Reds assured themselves of staying atop the NL Central with a 9-4 victory over Pittsburgh on Wednesday.

Rookie Juan Francisco had three hits and drove in a run in his second start of the season. NL batting leader Joey Votto doubled twice to raise his average to .324 after a sore right wrist kept him out of the lineup for two games.

Andrew McCutchen, back in the lineup 17 hours after being struck in the neck by a 90-mph fastball from the Reds’ Mike Leake, ended Cueto’s 18-inning scoreless streak against Pittsburgh by leading off the first with his ninth homer. The Pirates, as usual, did nothing after that against Cueto (11-2), who has nine of his 31 career victories against them.

“I like pitching in Pittsburgh,” Cueto said. “If I throw a home run, I’m OK. I say, ’Don’t worry about the home run.’ I threw my fastball, changeup, every pitch today was good.”

Cueto is 3-0 against Pittsburgh this season, throwing a one-hitter during a 9-0 victory on May 11 in PNC Park, and is 5-0 overall in his last seven starts.

Janish, filling in at shortstop for the injured Orlando Cabrera, hit a three-run homer during a six-run seventh inning against three relievers that made it 9-1. Janish had three hits, including a two-out, run-scoring single in the second off Jeff Karstens (2-7) after the Pirates chose not to intentionally walk him to get to Cueto.

“Obviously it’s a big injury, but we’ve got to deal with it as a team and I have to go out and do my part every day,” said Janish, who jumped his average from .269 to .300. “I know catching it and throwing it is my thing. Hopefully I’m able to swing the bat as well as I can and just contribute.”

Votto and Jonny Gomes doubled in runs against reliever Wil Ledezma in the seventh ahead of Laynce Nix’s RBI triple and Janish’s third homer, and only his second since April 14.

McCutchen caught his left knee in a patch of loose sod while trying to make a sliding catch of Nix’s line drive but wasn’t hurt — good news after escaping a potentially serious injury.

“I’m fine,” McCutchen said. “It (the homer) was a good way to start off. … But I’ve never slid like that before. I hope they get that fixed.”

The Reds, 10-1-1 in their last 12 series after taking two of three games in Pittsburgh, won their sixth in eight games overall as they enjoy being in first place this late in the season for the first time since the final week of the 1999 season. They own a one-game lead over St. Louis, which played Houston on Wednesday night.

“Yeah, we’ve got to keep winning series and hopefully you throw a sweep or two in there somewhere,” manager Dusty Baker said. “That’s when you get on a winning streak that we really haven’t had. We’ve been playing steady ball, but we’ve got a winning streak coming pretty soon.”

The Reds’ longest winning streak is five games, accomplished three times.

Cincinnati has won eight of its last 10 against the Pirates (37-70), who became the first NL team to reach the 70-loss mark. Pinch-hitter Jeff Clement had a two-run homer in the seventh against Bill Bray and rookie Pedro Alvarez hit a solo drive in the ninth for Pittsburgh.

The Pirates, fast closing in on a record-extending 18th consecutive losing season, are on pace to lose 107 games. Only one Pirates team since 1890 have lost that many games — the 1952 Pirates lost 112 times in a 154-game season.

Don’t look for the Pirates to schedule many weekday afternoon home games next season, either. They are 0-4 in such games this season, getting outscored 44-6 — including a club record-setting 20-0 loss to Milwaukee on April 22.

Notes: The Pirates have lost six of seven and 10 of 13. … The Reds are 31-18 against the NL Central. … Cueto is 9-2 overall against Pittsburgh. … Cincinnati outhit Pittsburgh 16-7. … Russ Springer, the Reds’ 41-year-old reliever, developed spasms in a hip muscle while pitching in the seventh. His status is uncertain.