The Arizona Diamondbacks decided to go young in their rotation, making a trade to keep 21-year-old Tyler Skaggs in the starting five.

Skaggs may want to take notes on Monday night when he is matched up against streaking Cincinnati Reds veteran Bronson Arroyo in the start of a three-game series.

The left-handed Skaggs made his major league debut on Wednesday, pitching the first game of a doubleheader sweep of the Miami Marlins. He allowed two runs, limiting the damage after giving up three hits and five walks over 6 2/3 frames of a 3-2 decision.

"It was pretty nerve-wracking but I felt like I did a good job," Skaggs said. "Trust me, everybody's going to have nerves, people say they don't, but once you get that first pitch out of the way you feel a lot better."

Though Arizona is still in the playoff hunt -- sitting seven games back of first place in the NL West and 6 1/2 out of a wild card spot -- it still opted to trade veteran starter Joe Saunders to the Baltimore Orioles on Sunday in exchange for reliever Matt Lindstrom rather than go with a six-man rotation to keep the highly-regarded Skaggs in the mix.

"We had six starters and with our young guys developing and performing here, we felt this was the correct move," D-backs manager Kirk Gibson said on his team's website. "We're going to keep Tyler in the rotation, just give him an exposure to the situation we are in, in a pennant race, that'll do him well for next year as well."

Arroyo has done it all over his career and is 10-7 with a 3.87 ERA in 25 starts this season thanks to an excellent seven-start run in which he has gone 6-1 with a 3.50 ERA. He won his third straight start on Wednesday, scattering two runs, three hits and four strikeouts in a 3-2 win over the Philadelphia Phillies.

"I was hitting my spots, both sides of the plate. I can't complain about anything. My breaking ball, sinker were both there," said Arroyo, who retired the first 14 batters faced.

The 35-year-old righty lost to Arizona on July 16 prior to his recent hot stretch, allowing five runs over three innings of work. That left him 4-5 with a 4.65 ERA lifetime versus the Diamondbacks.

Cincinnati comes into this series six games ahead of St. Louis for first place in the NL Central following an 8-2 loss to the Cardinals on Sunday.

The Reds, who lost just their second series since the All-Star break (9-2-2), got sixth-inning RBI singles from Chris Heisey and Ryan Ludwick. However, Homer Bailey was charged with five runs on nine hits with three strikeouts over six innings in the loss.

"When they start rolling, they really roll," Cincinnati manager Dusty Baker said of St. Louis. "It was a situation where they came in swinging the bats."

The Reds won't have first baseman Joey Votto for this series, but he is possible for the weekend. He is set to begin a two-game rehab assignment on Tuesday and hasn't played since July 16 due to left knee surgery.

Arizona fell to 2-5 on a 10-game road trip after getting swept in three games by the San Diego Padres. The D-Backs lost Sunday's finale 5-4.

Trevor Cahill took the hill for Arizona several hours after scheduled starter Saunders was dealt. Cahill, still pitching on four days' rest, was tagged for four runs on eight hits and three walks in just 3 2/3 innings.

Aaron Hill pulled the Diamondbacks within 5-4 with a two-run homer in the eighth, but the comeback came up short.

The D-Backs and Reds split a four-game series in Cincinnati from July 16-19.