(Sports Network) - Worst visits first tonight at Wrigley Field when a pair of National League Central rivals get together for the first of a three-game series.

The front-running Chicago Cubs - holders of a 5 1/2-game bulge in the six-team loop - look to extend that lead at home against the Cincinnati Reds, who've tumbled from the fringes of contention to the back of the pack since the All- Star break.

Taking the mound for the Cubs will be recent acquisition Rich Harden, who's made six starts since coming over from the American League's Oakland Athletics. He's 2-1 with a 1.80 earned run average in 35 innings with Chicago, allowing 24 hits and seven earned runs with 14 walks and 49 strikeouts.

In his last start, on Wednesday at Atlanta, he allowed two hits over five scoreless innings of an 8-0 Cubs win.

He was 5-1 in 13 starts with a 2.34 ERA for the Athletics before the trade.

Harden won his lone career start against the Reds after giving up six hits and four earned runs in 5 1/3 innings.

For the Reds, rookie right-hander Johnny Cueto can make it two wins in a row.

The 22-year-old Dominican had gone six starts without a win between July 9 and Aug. 8 before rebounding with a 3-1 defeat of the Pittsburgh Pirates on Thursday.

The first start of the winless string came against the Cubs, when Cueto dropped a 5-1 decision after allowing four earned runs and eight hits in 6 2/3 innings.

He's faced the Cubs twice in 2008, splitting two decisions and giving up a combined 14 hits and seven earned runs in 12 2/3 innings.

On Sunday in Cincinnati, Edinson Volquez hurled seven innings of shutout ball and the Reds salvaged the final contest of a three-game series with a 7-3 victory over the St. Louis Cardinals.

Volquez (15-5) put together his second consecutive strong start, allowing just three hits and four walks with four strikeouts.

Brandon Phillips hit a three- run homer while Chris Dickerson and Edwin Encarnacion had three-hit games with a run scored each. Jay Bruce added two hits and an RBI for Cincinnati, which won for just the fourth time in their last 16 games.

In Miami, Reed Johnson's three-run double highlighted an eight-run seventh inning, as the Cubs pounded the Florida Marlins, 9-2, in the rubber match of a three-game set from Dolphin Stadium.

Johnson finished 4-for-5 and scored a run for the Cubs, who have won nine of their last 11 games. Aramis Ramirez and Alfonso Soriano each drove in two runs.

Ryan Dempster (14-5) gave up two runs on five hits and struck out 10 batters over six innings to pick up the win. The 31-year-old is one victory shy of tying his career-high set in 2001 with Florida.

Chicago has won five of its nine meetings with the Reds this season.