DENVER — A heartbreaking sweep that knocked the Cincinnati Reds out of the top spot in the NL Central last week was expected to have a drastic effect on their mindset and playoff outlook.

The club is proving it won’t be going down lightly.

Back atop the division, the rejuvenated Reds look to win their fourth in a row when they open a nine-game road trip Tuesday night against the Arizona Diamondbacks in the teams’ first meeting of the season.

In last week’s highly anticipated home series against St. Louis, Cincinnati (67-51) was outscored 21-8 in losing all three games to go from leading the division by two to trailing the Cardinals by one. The empathic sweep seemed to signal a turning point, but the Reds are refusing to concede.

Cincinnati bounced back by sweeping a three-game series from Florida to retake a one-game lead over St. Louis, which lost two of three to Chicago over the weekend.

“We lose one, two or three games, and the young kids are learning how to come back from that,” Miguel Cairo said after Sunday’s 2-0 win over the Marlins. “It’s already in the past.”

The Reds, who have the NL’s second-best road record at 31-25, now look to keep it going with a trip out west.

Cincinnati outscored the Diamondbacks 26-9 in sweeping a three-game series in Arizona last season and has won five straight there. The trip will get much tougher with stops in Los Angeles and San Francisco, where the Reds are a combined 7-19 since 2006.

“It’s a law-of-averages road trip for us going west after all these years,” said manager Dusty Baker, whose Reds have won seven of eight on the road.

To kick off the trip, Baker will turn to Bronson Arroyo (12-7, 3.94 ERA), who is 4-1 with a 1.60 ERA in his last six starts away from Cincinnati.

Arroyo hadn’t allowed an earned run in 18 consecutive innings before giving up a two-out grand slam to Colby Rasmus in the fifth of Wednesday’s 6-1 loss to St. Louis. The right-hander departed after five, having allowed six hits and four runs — just the second time in eight starts he yielded more than three.

Arroyo went 1-1 with a 7.30 ERA in two outings against the Diamondbacks last year. The Reds were 5-1 in the season series as Joey Votto, currently the NL’s top hitter at .322, was 9 for 19 with four RBIs.

Arizona (47-72) is returning from a 4-3 road trip capped by Sunday’s 5-3 loss to Washington. The Diamondbacks dropped two of three to the Nationals to lose their first series since being swept by Philadelphia from July 27-29.

“I’d like to be 7-0. I guess it’s an improvement,” interim manager Kirk Gibson said. “We’re playing better.”

The arrival of Daniel Hudson (3-0, 1.59) is one reason the Diamondbacks are faring better.

Hudson, who will make his first appearance against the Reds, has yielded four total runs while throwing at least seven innings in winning each of his three starts for Arizona since being acquired from the Chicago White Sox.

In Wednesday’s 8-2 win over Milwaukee, Hudson gave up two runs and seven hits while striking out a career-best nine in seven innings. After giving up back-to-back homers to open the second inning, the right-hander settled down and ended up retiring 16 of the final 20 batters he faced.

“I thought he showed good composure coming back,” Gibson told the Diamondbacks’ official website. “He was in a couple situations there, where you can see again he has great composure. He makes his pitches when he has to and he gets out of it.”