D'Backs hope to slow down red-hot Reds

Veteran Bronson Arroyo comes off his best outing of the 2012 season tonight, when the red-hot Cincinnati Reds host the Arizona Diamondbacks in the opener of a four-game series at Great American Ball Park.

Now leading the National League's Central Division by a game, the Reds won their sixth in a row on Sunday when Scott Rolen slapped a tie-breaking, two- run single in the bottom of the eighth inning to help the Reds beat St. Louis, 4-2.

After the Cardinals put the first two runners on in the top of the eighth but failed to score, the Reds took advantage of their opportunity in the bottom half.

Joey Votto worked a one-out walk before Jake Westbrook (7-8) plunked Brandon Phillips. A fielder's choice groundout moved both runners up and Ludwick followed with a four-pitch walk to load the bases.

Rolen then served a fastball from reliever Mitchell Boggs over the head of a leaping Skip Schumaker at second to plate Votto and Phillips.

"You try not to make it a bigger at-bat than it is," Rolen said. "You try to get a good pitch and put a good swing on it."

Aroldis Chapman fanned all three batters in the ninth to nail down his 13th save of the season.

Homer Bailey (8-6) allowed two runs - one earned - on nine hits and two walks over eight strong innings and has now allowed just five earned runs in 22 2/3 innings over his last three starts, all of them wins.

Votto and Phillips both knocked in a run for the Reds, now a season-best 12 games over .500.

Tonight it will be Arroyo, who in his final outing before the All-Star break, tossed the 13th complete game of his 344-appearance career and emerged with a 6-0 defeat of the San Diego Padres on July 6.

In the win, the 35-year-old Floridian allowed three hits, walked a batter and struck out eight while trimming his earned run average from 4.06 to 3.73.

It was his first win since June 15 after a loss and a pair of no-decisions in three subsequent outings.

Arroyo is 4-4 lifetime against Arizona while posting a 4.14 ERA across 68 2/3 innings.

The Diamondbacks counter with second-year lefty Wade Miley, who makes a third attempt at reaching double-digit victories in his first full big-league season.

The 25-year-old debuted in the majors last season and appeared in eight games while going 4-2 with a 4.50 ERA in 40 innings.

He began this year with nine wins in 12 decisions, but has dropped consecutive starts at Milwaukee and home with the Los Angeles Dodgers while allowing 16 hits and 12 runs in 10 2/3 innings.

Miley has never faced the Reds.

On Sunday in Chicago, Matt Garza fired seven shutout innings, while Darwin Barney smacked a two-run homer, helping the Cubs down the Diamondbacks, 3-1, to complete a three-game sweep.

Trevor Cahill (7-8) surrendered three runs on four hits and three walks for the Diamondbacks, who have dropped nine of their last 12.

"It's frustrating that we either play well or we don't play," Arizona manager Kirk Gibson said. "We're very streaky. We just haven't had quality at-bats."

Arizona won two of three from the Reds in an April series in Phoenix, then won another two of three the following week in Cincinnati. The Reds won the 2011 season series, 4-2.